I'd like to see new presents (10-15 new to add the variety), biomes, and maybe another one or two characters that can be linked back to the original games if there's enough time to focus on them. I'd be willing to pay for this content as well, but I do feel it's important NOT to split the community up over it (eg: eliminate the potential for "you can't play with people unless you have the DLC").
The way that these menus are set up, you have to scroll up and down to find what you want, which is kind of annoying and will become more annoying if you guys add more stuff in 2.0 and beyond. Scrollin' for days.
It would be so much easier to navigate if they were set up in a grid format, and is more aesthetically pleasing to see how much you've unlocked at a glance.
This is more of a 2.0/DLC request:
Would be fun to unlock new colors for each character's clothes when you finish a run, maybe limit it to Random+ modes and above, or have a new color/pattern/etc unlock for each mode type.
This could be DLC or just an update. Would love to have some more Earthlings, I miss the hamster in a ball from the original game.
@Nap: Would pay for extra DLC content :)
Our entire menu system could use a bit of polish