I have a few UI compliments and some suggestions for polish/improvement to share:

Game Setup Screen - So I want to start off by stating the redesigned UI elements in the game setup screens are 1000% better than the UI was before. Not only are they clearer, but they're also much more visually appealing.

Planet List - Thank you for adding right-click functionality for sending selected fleets. This helps get around one of the bigger navigation headaches created by sectors. Would you consider adding a list of waypoints to one of the tabs (perhaps the "Fleets" tab?) on the right and giving similar right-click functionality to it?

Ideology Screen - The ideology screen is improved as well and with the changes to ideology, it's great that the screen tells you which side your empire leans towards on each ideological pair.  My only suggestion here would be to more clearly display the total Ideology Awareness.  I only discovered today that you can see your total awareness by hovering over the Ideology title in the upper left on each half of the screen displaying a particular ideology pair.  It's a minor suggestion, but I'd like it better if the Ideology Awareness was displayed not only in the tooltip, but also right after the Ideology name, like so:  Compassion - 4 or Cruelty - 1.  It's important information for the player, and really shouldn't be buried in a tooltip, imo.

And that gets to the root of my issues with certain UI changes.  Information that is important to/used by the player should not be buried, limited to hunting through a hundred tooltips, or outright removed.

Ship Roles/Ship Tooltips - Per the 0.65 release notes, Ship Role information was removed from the ship tooltip.  The problem with this change is that there is now no way to identify the role for ships that I have not personally designed.  Ship Roles, as I understand them, affect how a ship behaves in combat, and (unless this has changed from GC3) in what order it is targeted by other ships as well as how it targets other ships.  What this means for how I play the game is that the Escort/Capital role pairing is essential to preventing my offensive ships from being blown away before my defensive screen.  If I cannot tell what Ship Role is assigned to the Command and event ships I've not personally designed, I cannot be sure that I'm balancing my fleet composition the way that I'd like.

Please feel free to let me know if I missed a change that's been made to how Ship Roles function. Especially one that would somehow make this information irrelevant. But since we can still assign ship roles during ship design, my best guess would be that is not the case and the UI team failed to understand this particular consequence when they removed Ship Role information.

Govern/Databanks Screen - Removing the list of planets that had production outputs displayed on it removes easy access to information from the player.  For example, I can no longer determine at a glance which of my planets to specialize into which role or where to put that new science wonder I just unlocked.  Instead, I now have to rely on the Core Worlds portion of the planet list in the upper left corner of the main screen now. While its sort function is workable, I can't see and compare the production of each world without checking tooltips one-by-one, and having to remember each world's outputs.  A list of worlds such as the one that used to be in the Govern screen is absolutely essential for managing empires that span more than one sector, and a great convenience for managing smaller empires.

Orbital Mining Highlights the Lack of at-a-glance Resource Display - Most 4X games try to make it easy and obvious where resources are on the map, and GCIV does well with strategic resources like Antimatter and Elerium... when they're floating free in space.  But put a deposit on a size 7 planet in a Huge sector, and then the player has to hover over planet after planet parsing tooltips to figure out which planet has that Elerium or Harmony Crystal or Monsantium deposit they need to build an orbital extractor for.  Or which planet to colonize for that resource, for that matter.  Since a recent patch changed it so that planets can now only have one resource, it would be awesome if the planet had a small resource icon on/overlapping it, on the lower right arc of the planet icon circle perhaps.  Failing that, the icon should be displayed in the planet list.  Or even better, in the restored list of planets that you'll hopefully be returning to the Databanks screen?