I'll try to update this when I encounter less-than-perfect end user experiences when using a controller as the primary input method.
* "Flee or Fight?" dialog requires keyboard and mouse input. This makes the game impossible to play through without using the keyboard and mouse. I think this is probably the highest priority controller issue since the rest of them are just QoL issues.
* When two controllers are connected, please assume by default that both controllers should be used when in fleet battles. Having P1 be both controller and keyboard/mouse is fine.
* When launching the game, have the default selection be "load" instead of "new". Or add a "continue from last save" as an option and have it be default. (link to forum post on it https://forums.stardock.net/491082/page/1/#3727594 )
* When buying/selling materials, it is not a smooth experience (for me at least). To highlight the first item in the inventory, right or down has to be pressed on the stick twice. I believe that the first item should be selected by default, or at the very least have the input be given only once (two stick presses and a button press for each sell is tedious). Also potentially have the "sell all but the valuable stuff" be more prominent and easier to select without many joystick presses.
* The star map. Selecting systems for autopilot is not fun with a controller. How about have it automatically "snap" to the nearest system in the direction of the stick press? Using the analog stick as a mouse is not a great end user experience. There is some snapping, so that is good, maybe a quick "fix" would be to expand the radius for snapping? Or maybe just have it cycle through the star systems when a direction is pressed?
( https://forums.stardock.net/491239/page/1/#3727955 )
* In fleet battles with two players using controllers, player one can cancel player two out of their menus. (anecdotal, it happened to me a couple times, I'll test again next game night)
* Some players might prefer using the d-pad instead of the analog stick. I know that controls can be custom set, but is it possible to have both the analog stick and the d-pad both work for ship movement? There is value in having the d-pad for online multiplayer chat antics, but I believe that player input for steering is more important. If analog and d-pad can both be used interchangeably that would make local multiplayer fleet battle sessions a lot more appealing for groups that disagree about which input method is best.
I'll edit this post and add to it as a slowly play through this game.
Sorry for not posting it prior to release.