I really like this idea. Especially the idea of buying an opponents debt and getting their interest. However, pro players just seem to ignore debt for the most part so they would really have to make debt more relevant to the game at large and not just the stock price.

Unless, the loans have a repayment trigger, or a maximum time allowed before being repaid. This would force players to manage loans and payments and even allow for selling bonds to other players. 

I like this idea. It gives you a good way to generate income. It also starts making Debt a risk factor, because ultimately you could be sending your competition money eventually.

I know it's your first stab at this. Again I do like it, but I'm going to poke a hole in it. I'm doing this because I would like to see it make it into the game.

I buy cash. Then purchase stock, and win the game in two minutes.

See the problem is where does the initial pool come from? If it's not a quantity that's available from the game, like how you can buy steel all willy-nilly, then Someone has to buy into that. The chances are that if you're the person with the cash, you've probably got other plans for it. Now As a player and real life if you put it into a bond or other asset, suddenly it's not liquid. I've bought someone else's debt, right?  Unless you sell the debt to someone else you can't get it back right away if you need it. You must wait for it to be repaid right? Or are we assuming those that bought into the debt will get paid dividends from interests payments? 

There should be a threshold of debt that your company can carry on it's, proportional to the total value. if you exceed this ratio it should send your stock price tumbling. That's what happens in the real world. Anything beyond that someone has to buy that "new" debt. There needs to be a payoff period, and they can take it in stock or possibly in resources. Say the most expensive/necessary ones first.

So here's my first stab at a counter. Hopefully, this will get your brain surging onto a better idea to limit this than mine. 

I really do like this idea, but we also have an issue with time. These games are supposed to be over in 30 minutes or so. That's the goal at least. So you would have to pay it back in say 5 minutes or something, and you may not be able to do that.

Mow that I think I like the idea of say people or the lender getting stock in your company. You could potentially loose and get bought out by carrying too much debt, so the computer takes over your company and instead of the buy out notice, you have to sit there and watch all of your claims and debt be auctioned off at a fraction of the price.

Cash/debt management is one of the first things I brought up after playing my first few games. I also suggested that interest rates should go up the higher your level of debt is and that players should be able to buy that debt to earn interest. 

Right now this is an excellent game and honestly if no changes are made at all I won't be too disappointed but having more ways to use debt/cash as a weapon would be a great thing and the current way that stock buying and debt work have a couple of game mechanics systems problems that I see:

1. There is no "counter play" to someone buying your stock - I mention this below but if someone is buying your stock the only valid response is to buy their stock faster, you can't defend against it by buying your own stock and unless your really close to getting OFT buying anyone elses stock or trying to build anything else is sure death. Basically as soon as someone starts buying you need to dump everything, crash the market and put your cash back into their stock and race them to a buy out
2. There is very little strategic reason to buy a few shares of stock - you basically go for the kill or use your cash for something else. Again there are a few exceptions to this (someone getting 200k of debt and tanking their stock price early) but for right now people stock pile cash and then come out swinging for blood - their are two exceptions to this I can think of. 1. if you see someone else about to get bought out it's worth buying into those shares as once the other guy finishes the purchase it give you a huge chunk of cash you can turn around and use against him, and 2  I do want to experiment with spreading out and buying a few shares of several peoples stocks just to be closer to the kill if they decide to start buying me, but if I'm far ahead enough to afford to do that I'm still better off just buying one person outright 
3. the consequence of debt isn't harsh enough -  most games I've won I've had the most debt in the early to mid game by a large margin (30-70k by mid game teir 3 when most others are debt free or <10k) yes there are a few notable games I've played with counter examples to this mostly when I was able to get an early monopoly on energy and everyone else just forgot to get any, but still as long as your spending your money wisely the more debt you can get the better and I've almost never bothered to voluntarily pay off my own debt, the money is almost always better spent somewhere else, someones buying you? You can increase your stock price faster by buying them back rather than paying off your debt, resources are crazy expensive? Get more debt to get more plots to make more resources. The markets flooded and resources are <$5 then you either have an offworld market and your going to win or you stay in debt to buy an offworld market 
4. There's almost no strategic reason to buy your own stock and so there is never a time when you'd sell you own stock

Here's how I would change debt:

• just like every player has 10 "shares" of stock that can be bought, every player would have 10 bonds that could be bought (just duplicate the share buying UI boxes right underneath the stock boxes) Each bond is worth 1x-2x times the stock price. So if it takes 5k to buy your share of stock (start of the game) the first bond hits the market at 10k of debt. And this scales with stock price so your stock is $20 then your bond is 40k of debt.
• right now the only way to voluntarily go into debt is through auctions or buy selling everything and then auto buying life support, it would be nice to voluntarily sell the first 3-5 bonds for their cash value
• For each bond you have out your interest on all of your debt goes up 2% so 10% for the first one and 30% for the 10th one. Yes this is really harsh but so is your interest compounding every night, it is a simulation game after all.
• Your bonds can't be bought until your in debt (just remove the boxes from the UI but have them fill in as you go deeper in debt) this would provide a nice clear visual indication to other players how much debt your in in relation to your stock price.
• If your bonds are bought you pay interest to the owning player every night. (instead of into the ether) but the interest you pay is subtracted from cash first not added to your debt the way it is right now. And honestly even if no other changes to debt are made this is one change that I think should be made. The idea of a debt service payment.
• once you have 5 bonds out the game option of "tighter debt" automatically kicks in so at a stock price of $5.00 once you hit $50k of debt all of your expences are subtracted from cash first 
• at all 10 bonds revenue goes to paying off debt first, so basically extra tight debt, again at a $5 stock this would happen at 100k of debt, at a $10 stock this would kick in at 200k of debt, at this level of debt your basically locked at 0 cash until you get back down under the threshold.
• If you own someone elses bonds when that persons stocks are bought then part of the buyout price would be to pay off your bonds at 2x the cost (just like stock is now) so owning someones bonds kinda protects them from being bought by anyone but you
• If you own someones bonds and they are trying to buy YOU out your buyout price includes 3x their bond price - this stops someone from diving headlong into debt to buy you out, you can counter it buy buying their debt at the same rate they are using that debt to try and buy your stock, they are basically forced to pay off their debt to you before they can complete the buy out

 Here's how I'd change stocks, mostly aimed at more counter play defencive options and more reason to trade in your own stock:

• have 20 starting shares of stock 10 of which you own and 10 of which are available to be bought (representing the initial shares of stock that where sold to finance the expedition)
• all selling transactions of goods(or profits from energy entertainment etc.) pay dividends 1% to each share, so at the start of the game you own half of your shares so your paying a 10% haircut in dividends to the market for your 10 unowned shares.
• increase the stock price multiplier 2x-3x for owning your own shares of stock, right now buying your own stock is not actually a defensive move as the cash you spend doesn't actually increase your stock price enough to protect you from buying you out. You might have slowed them down, but the only way to stop them is to buy them out instead. Spending your cash on your own stock slows you down from buying them out by the same amount that it slows them down from buying you out. Really the only defense is having a team mate buy your stock (as then they get 2x the money if you are bought in full and can use that cash to buy the person that bought you)
• Increase the time between stock purchases to 20-50 seconds, right now once someone begin buying you there is very little time to react if they have the money to end you then there is nothing you can do about it, there is simply no time to react and retool. If instead it was 30 seconds between stock purchases (for the same stock only) and they own none of yours at all then its a full 5 - 7 minutes before they can complete the buyout, thats not a huge amount of time but it's something, this would give people more incentive to buy a few shares early (to decrease the total time needed) and to spread out the purchases over several people

So the start of the game do you want to "rush" by selling off your shares and bonds and start with more cash? (but driving your stock to $1 and risk being bought out at teir 2) or worse risk giving away a huge chunk of your revenue in the form of dividends, are you weakly in the lead but don't want to target someone for fear of being dog piled on, then buy your own stock (increasing your profits because your paying out fewer dividends) buy other peoples debt to earn interest and protect against someone rushing buying you out, this is a non aggressive way of strengthening a lead, spread out and buy a few peoples stock, thus reaping some of their dividends.

Anywho this turned into way more of a wall of text than I thought it would I think I'll stop there