Hi, I am big fan of Hidden in Plain Sight and I am developer of Overlook.
With Overlook we want to push Hidden in Plain Sight to next level with:

* Game supporting for up to 16 Players
* One hand required to play game (so you can hold drink in another)
* More game modes and dynamic configuration tweaks (profiles)
* Beautiful graphics

If you like idea, please support us on Kickstarter!

http://store.steampowered.com/app/345180/

http://store.steampowered.com/app/239070/

http://store.steampowered.com/app/258970/

also this http://store.steampowered.com/app/35130/

and this http://store.steampowered.com/app/350740/

this http://store.steampowered.com/app/399820/

We're just about to launch our new game Fragmental through Early Access, and would love it if you'd take a look.

Couchplay: Yes
2-4 players: Indeed
Lightning fast gameplay, perfect for a party: Absolutely
Co-op: Ummm, kind of. Team deathmatch and other game modes are planned, so lets leave this answer vague for now :-)

http://store.steampowered.com/app/424040

http://store.steampowered.com/app/57680/

http://store.steampowered.com/app/247950/