- I'd like a new class or two. Maybe something that utilizes Chrysalid or Muton physiology to make a melee focused soldier or something that focuses on hacking robots.

- More maps. I'm pretty sure I've seen them all at this point.

- More hat/helmets. I need to make Jessie Ventura from Predator. Nickname: Sexual Tyrannosaurus...

8 or even 10 person squads.

Some sort of Co-Op could be interesting.

Aliens that give you hugs.

A mod that turns it into a 40k game.
Realistically more single player maps would be cool. More stuff to research. Co-op would be rad.

More enemies!

What I want most of all: Skirmish mode. Let me pick a map, select battle conditions/randomize everything, and jump right in to a fight.

- Making mouse and keyboard playable without pathing fuckups or flickering in multi-level spots
- Removing the random spawn right in the middle of your people for no reason bug that can wipe out entire squads 
- Balancing panic/aim/crit/health/funding/building based on customer input and what the mods have tweakad
 
..after that I'll take any DLC they offer! :(

Fix the goddamn mouse/keyboard functionality. It's become so frustrating late game that I'm finding myself even losing soldiers on occasion because, in trying to find JUST the right combination of height view and angle so I can actually click on the spot that I want to take cover at, the tiny little window that the game allows me for that particular spot can cause me to accidentally click on adjacent squares. This leaves the soldier completely in the open, flanked, and then dead. Playing Ironman that way is just a pain in the ass.

Oh and more armor

It'd be cool to see the base animate and populate a bit more, and fill up with your actual soldiers. And if they were injured, they'd show up in the medical bay.

Some sort of language pack for multinational voices.

More maps, more armor, more guns.

A skirmish mode like the above guy said.

I'm still working through the campaign for the first time, but I wouldn't say no to more content!

Some sort of coop would be great.

I hope they make expansions, like the ones we had back in the 90s, not the 1 dollar skin packs we call DLC today.

I also hope there will be no focus on multiplayer DLC.

@SomeJerk said:

- Making mouse and keyboard playable without pathing fuckups or flickering in multi-level spots- Removing the random spawn right in the middle of your people for no reason bug that can wipe out entire squads - Balancing panic/aim/crit/health/funding/building based on customer input and what the mods have tweakad ..after that I'll take any DLC they offer! :(

• Mouse interface fixes is my number one complaint. Maneuvering around the bigger UFOs with a mouse is an exercise in frustration
• I think I had that random spawn bug, but then again it was a Cyberdisc that just appeared when I didn't have visibility on the downward ramp. I'm not sure if he randomly spawned or if he was hiding. Those guys are sneaky...
• I think panic/aim/crit/health/funding/building are balanced just fine on Classic.

As for the question the OP asked, I wouldn't mind a Terror From the Deep style campaign.

Options for free aim and limited ammunition would be nice, as well as hitbox detection on shots.

But that's probably too baked into the code to change for an expansion.

Wouldn't mind some DLC missions with the theme of the 2nd Xcom game of going underwater.