You could always get 5 and try it, and sell some off later on if really needed. I didn't know if you were taking angels out or not. Though the tank's footprint really isn't ideal, it could probably work. I'd just make sure there is some open areas they can hand out around or close to the bottem.
I've never kept anything other then clown loaches, so as to their compatibility....no idea. I'd only think it'd be a problem during breeding....but i can't say for sure.
The corys, well idk....if they are fairly large they should be ok (though again, unsure especially during breeding). Geos have been known to eat small tetras before so anything that small is at risk.
I'm a risk taker, a lot. I like to cut corners and try new things fish stocking wise. So coming as my opinion......go for it. Give it a shot, if it becomes a problem take them out of there.