Here's what I'll miss:
Being able to use Combo Overhead Camera with WASD.
Turning radar mode on automatically at battle start, but not when speccing.
Making adv. playerlist not clutter the list with spectators when playing.
Chili core selector moving the camera to the factory position with right click instead of left click.
Los colors that -only- show radar coverage, since I think it's far more important to know where your radar coverage reaches than what your units see - and the default los mode, which shows both radar and los, is just way too ugly with all the random colors. Also I have /dark and /bright commands to adjust the brightness of the los shadows on excessively dark/bright maps.
Chili chat hides spectator chat when playing in a team, but not when speccing/watching a replay, or playing 1v1 or FFA. This way I can focus on ally chat in a teamgame, instead of getting spammed by some balance discussion that specs are doing with global chat.
Binding building starter (nanoframe) widget to a different key than Q.
Since I use WASD to scroll, I don't want to use the gesture menu with keyboard. But I don't like the way the mouse-only gesture menu interacts with multiple cons (especially if I have two comms and wanna push with them side by side). So I use a hybrid mode, in which Q opens the gesture menu, but only mouse is used to select the building to construct.
Unit shapes widget modified to show a teal circle around unselected cloaked units that you or your allies own. Makes seeing them immensely easier, especially with luashaders=0 where there's no special cloak effect.
Receive units indicator playing a sound when getting units. Without the sound it's just way too easy to miss that you've received some units.
Holdfire fix, that makes units stop shooting immediately when put to hold fire, instead of still trying to finish their last chosen target.
Cloak fire state widget not affecting the commander. It's not fun to use a sniper commander if the widget constantly puts it to hold fire.
These tweaks are accumulated during a long time span, usually as a result of me losing a game because of UI difficulties. So nothing earth shattering, but they make playing immensely smoother for me.
Some of this is probably worth committing, like the widget that makes cloaked units easier to notice, but it'll be some work for me to get epic menu to recognize these options - since most is stuff that probably won't be on by default.