Ideas.

These aren't story ideas... just ideas for Deadpool in the future... in Videogames. 'Nuff said.

Kingdom Hearts.

Simply put, he's more or less a secret boss you can fight in a Marvel level. Sora & the others approach him.
Hmm? What's this!? The player has found me, a secret character!?
Uh... hi? Who are you? You're no one we've seen before.
The name's Deadpool! Rhymes with 'Old School' 'Too Cool' 'Ain't no Fool' and 'I'm the best there is what I do'!
... Ok?
Gwarsh, he kinda looks dangerous.
Dangerous? He's annoying!
Well at least I don't have a speech impediment.
WHAT!?!?!?
And I'm no Dog thing that gets too much bumps on his head.
Hey, that's not very nice.
Or a Teenage boy that goes around in dorky clown shoes! I mean, look at them, folks at home! How big are his feet!? I hope you're not some sort of bigfoot person, are you? Know what, maybe I gotta contact the developers of this game to makes your feet not so freakin' huge!
What-!? Who are you talking to!?
The player, of course! They're probably recording this very cut-scene right now, followed by the battle, in which I'd beat you, or, more than likely, they beat me, followed by our final cutscene, and upload to the internet. Oh, and Hi Sora's parents! I'm sorry if I hurt your son.
Ugh! Enough of this!
Ooh! Boss time! Let's play... Rowdy Rumble!

*Deadpool fights, taunting the player into using their items, alters the controls a bit, teleports & shoots at the trio, uses his Katanas, dances away, and blocks the camera with a hand.*

Deadpool falls to the floor.
Can you shut up, now!? Deadpool teleports behind him and laughs
That was fun! You got me REAL good there, player! That grinding must've REALLY helped you... or are you some sort of gamer god?... Eh, who cares, you won, yay for you! Be glad the developers didn't add in my healing factor. Oh, here ya go, Sora! An Achievment for beating me, with this new Keyblade thing I have for some reason. He teleports away. See you in the next game!
... Most... annoying guy... ever.

El Chimichanga. Most OP Keyblade... and most annyoing.

Own game ideas.

FPS-ish

A game that will play a lot like Dishonored... but with Marvel and Deadpool sense of humor. Plus, multiple endings (Good-Good, Good-Evil, Evil-Good, Evil-Evil)

Hack & Slash.

Devil May Cry gameplay. Also, able to play as Lady Death, Psylocke, and, if produced by Capcom, Dante.

Sand Box

Infamous-ish, also with different endings... and choices do matter, not just the ending.