FE's UI is overall pretty good, but the UI can be a bit too tiny at times. I've played other games that will scale the user interface up or down via a preference (most recently, Dungeon Defenders). So, you could choose to increase the UI size by double its current size or maybe even reduce the current one (though it's rather minimal already).
Justification for the scaling:
*Unit icons in cities are way too small. You can barely click on the tiny up arrow to ungarrison them.
*Selecting units for spells/effects is a very small screen.
*This improves accessibility for people with poor eyesight.
*While the general screen is good to look at, I can't see it all simultaneously anyway, and I interact just as much with the UI as I do with the units on screen.
There's currently unit scaling in the game. How about UI?