I recently purchased entrenchment and after having played a few games I've noticed that the Starbase upgrades don't seem too well balanced, particularly when you consider that many of them need to be researched in addition to being built against the 8 slot limit available to a starbase.  In particular certain abilities stand out as being pretty weak and noth with the research time/development cost/upgrade slot on the starbases.  Here's the ones that stood out to me as being pretty pointless

The vasari repair starbase repair ability seems useless.  It's one more thing to research on the defense tree (taking time away from other more valuable topics) and the result just seems to allow the starbase to slowly self repair during a fight.  It's not clear if spending the second point in the ability even improves it significantly or even at all.  Either way the upgrade slots would be better spent in the generic defense upgrade which makes a starbase massively more survivable than this repair ability particularly if you max it all the way to the 4th level.

Another ability that all the starbases seem to have is a planet denial upgrade that prevents an enemy from colonizing the planet you built the starbase around.  I really don't understand how this would ever be useful given the cost of research and spending a slot and resources to upgrade a starbase with it.  Am I missing something here?  What's to stop an enemy fleet from coming in and destroying the planet anyway (avoiding the starbase).  Simply denying colonization seems pointless if it fails to prevent the planet from being bombarded out of usefulness in the first place.

The advent starbase has a culture broadcast upgrade for their base the seems fairly pointless as well.  I've never seen anyone win a game with culture anyway, it's the space battles that always decide the multiplayer games I've done.  Culture defense techs pretty much ensure it's trivial to catch and halt a culture push before you lose a planet to it and even if you did lose a planet you wouldn't lose the orbital structures and the opponent wouldn't actually capture the planet so it's fairly easily fixed, again better off spending those slots on the meteor thrower or destabilizer.

The TEC safety override protocol is another seemingly pointless upgrade.  The major cost of implementing so situational an ability seems pretty pointless.  It also seems like it would be fairly predictable/avoidable by simply sieging the TEC starbase from outside the range of it's detonation or simply commiting the minimum required forces to defeat the starbase even if they use the ability the attacker's goal is still achieved as the base will be gone.

It's also interesting to note the economic upgrades are rather imbalanced as well.  Vasari gets colony pods which while rather expensive produce a nice economic boost to drive their war machine in a late game scenario.  Advent gets the 30% allegiance boost.  This upgrade can be particularly good since it'll scale with the economic output of the planet and structures in the gravity well espescially if they are further out from the homeworld, like a desert planet loaded with trade ports that would normally cap at 35% allegiance suddenly almost doubling to 65%.  But TEC gets the shaft here all their starbase only capable of being fitted with repair bays/shipyards, which is at best maybe gonna free up a logistics slot to throw down another trade port. 

Finally there's the issue of mobility of the Vasari starbase.  This gives it an incredible advantage allowing to to very effectively defend against attacks while the other races simply have their bases simply get flown past and watch helplessly as the planet is bombarded from the opposite side.  What adds insult to injury is that this movement capability is baseline, requiring neither research nor a starbase development slot/resources.  Perhaps to balance it, the Vasari starbase should have to switch modes between mobile/immobile carrying some penaltys while in mobile form (offensive capabilities restricted perhaps) or conversely giving this option to the other races starbases but with lesser or no restrictions on the vasari.