Hey, I had some interesting ideas for SC2's interface that I thought would be handy. Some might fit better in a less-competitive RTS, so I've marked them as such. I'm mostly looking at multiplayer, but I think all of these could apply to singleplayer as well.

-In addition to a minimap, have a full-screen map overlay that works the same way that only appears when you hold a certain key (tilde would work as shift and ctrl are taken already). It's difficult to click the minimap accurately at a quick pace (especially above 120apm), and this way you can select your units, hold tilde to bring up the map overlay, click on the map overlay where you want them to go (just like the minimap) and then let go of tilde so the overlay won't get in the way anymore. (this is my best idea, I think)
-Completely configurable hotkeys (a la Sins of a Solar Empire) and ability to save hotkey configs.
-Unlimited group and location hotkeys (if you configure them).
-Option to use hotkeys in a manner sort of like C&C (if I remember right, use the location of the icon in the build menu to define the hotkey instead of a letter in the name of a unit).
-Hold a key (maybe spacebar, where tapping it goes to the last alert), the hotkey for creating a unit (T for Siege _T_ank for example), and dragging a box to select only siege tanks. This wouldn't work if some units in one race shared build hotkeys. Also wouldn't work on custom maps with multiple races that share build hotkeys.
-Use Tab or Alt or something to show unit health in bars (a la WC3, might already be in SC2)
-Option to disable alt-tab and Windows key while SC2 is open
-Select multiple buildings (like WC2) (allows focus fire for towers, mass rally points, send multiple build commands at once, liftoff lots of buildings at once) (drag select should default to units, only select buildings if no units are in the box)
-Pretty sure this is already in SC2, but remove select limit (be able to select more than 12 units, seems an arbitrary restriction)
-APM counter while in-game, not just replays (why not?)
-In-game clock, game timer (might affect gameplay, but still a suggestion)
-Option to record FPVoD in replay (would have to record all mouse movements, but it'd be cool!)
-Probably already in SC2, but multiple AI difficulties
-More interface configurability in general (maybe WoW-like addons?)
-Windowed-mode
-Replay converter that can convert replays between versions (or make all replays work on all versions)
(took a bunch of these from current SC plugins)
-Remove patrol (does anyone actually use it? the only thing I use it for is vulture micro, attack-move could be programmed to do this sort of idea)
-Formation ability (or at least make the magic box more known) (would also eliminate need of larvae trick, since you could disable formation and have flying units stack) (have hotkey for toggling formations, save formation or not in control groups)
-I think this is in SC2 as well, but graphs like bwchart (build order by time, cash by time, APM by time, units by time (individual and total), micro and macro APM, etc...)
-Ability to zoom in and out with mousewheel (a la Sins of a Solar Empire to a much smaller degree or WC3 with more ability to zoom out)
-Shift-queue buildings (a la WC3, most any recent RTS)
-Ability to assign hotkeys with a button other than control (like middlemouse or something so you don't have to stretch across the keyboard, not a big deal but I'm not that great and it slows me down a bit :) )

Stuff that not make sense in a competitive setting because they lower required APM (though makes some minute/boring things less of a pain):
-Make workers that pop automine minerals if the town hall is a minimum distance from a mineral patch (only minerals, not gas).
-On making a worker mine, make it automatically figure out which mineral patch is being mined the least and have it mine.

What do you think?

1) interesting idea
2) would be really nice
3) Don't really think more than 16 would be necessary esp with bigger group caps, but maybe a few more than 10 would be nice if the hotkeys are configurable.
4) Never played C&C before, but descriptions sounds like something that I've suggested before
5) Interesting idea, don't know how useable it would be though. And would probably be difficult to implement
6) Sounds like this is already in the game
7) Would be nice, but buying a gaming keyboard solves this problem. It'd be nice if it could be used as a hotkey or for some other purpose though
8) Already in the game
9) I think there's still a limit, but it's much bigger (like 30 i think, and more than this would just make selected groups difficult to maneuver)
EDIT: after some additional reading it sounds like the limit has been completely done away with and you can select unlimited units.
10) As a toggle maybe, but not really necessary
11) I rather they not, but if they do it should be part of the command bar (I'm referring to the entire panel at the bottom of the screen). Maybe it could be a minimap toggle (more useful that show/don't show terrain at least)
12) This would be kinda cool and esports friendly, but I don't see the common player using it much.
13) SC1 has multiple AI difficulties, but you have to use trigger to activate them. It'd be nice if you could select the difficulty in the game lobby.
14) Not for SC.
15) Why?
16) Do you mean like SC->BW and vice versa, or is there some other form of replay I should know about?
17) Patrol is quite useful when you want units to guard an area, but not be sitting ducks
18) Although I kind of like this idea, I don't think it fits well with SC. Formations would somewhat diminish the effects of micro
19) Cool charts are always a plus. More info than we get at the end match of SC1 would be nice
20) Might be nice to zoom out for seeing larger portions of the battle and zooming in to be able to select individual units more easily, but I think the static zoom level is more esports friendly.
21) How exactly does this benefit buildings with a build queue? And how would the handle queue commands that used more larva than available for zerg? And this would potentially be a ridiculous advantage for the protoss warp-in by giving the back a build queue.
22) Wouldn't be a problem with custom hotkeys, or if they refrained from using the 1-0 hot group set-up.

Stuff that not make sense in a competitive setting because they lower required APM (though makes some minute/boring things less of a pain):
1) Already in the game
2) Already in the game, worker AI is vastly improved in SC2.

10) Definitely as a toggle.
12) I feel from the battle reports that they are trying to make this as esports friendly as possible. :)
15) Why not?
16) Between patch versions of the game. I have a bunch of Brood War replays from years ago that don't work in the current patch version.
18) Agreed, but the magic box concept is sort of bizarre and I feel it could be improved.
21) I mean you select a worker, hold shift, tell it to build a CC and then a supply depot, then it builds the CC, finishes it, and starts the supply depoy.

12) After some additional reading, it sounds like FP view is recorded as part of the replay already.
15) Allowing a windowed mode would probably make hacks easier to toggle on and off, which could make cheating easier to get away with.
16) Having not used the replay feature (I haven't played in a long time, and when I did play, I was too naive to realized the advantage of using the replay feature), I hadn't realized that replays from past patches couldn't be watched on games with the latest patch.
21) That makes more sense now that you clarify it. This always did make me wonder. If you tell a worker to start building, you can queue another command like movement or resource gathering if you do it before the worker starts building. So, I dealt with the problem by always taking a worker from the resource line, giving a construct command and following with a queued command to gather resources. Probably not the most efficient tactic, but it keeps me from having stray workers.