Others ideas for Santa Ashley :
Priority -1 : (more critical than 0 )
30 FPS MODE (or the ability to fix the framerate/frameskip) :
The last time this was tried the engine effectively collapsed on itself, C2 is fantastic, but the more I read about other users experiences (my work is on mobile, where FPS isn't a massive deal) "50+ FPS or go home" seems really apparent.
Just throwing my 2 cents in, looked at Stencyl after reading about Haxe, they've got a great UI where things like sprite windows are displayed as tabs - I'd actually quite like that for C3. If only to get rid of having to resize and drag around the frame window/image canvas because they stack on top each other...
In regards to C3, I welcome it, though the inevitable 6 month drought makes me sad. In an ideal world C2 would have modurality so the community could "take over" C2 development as Ashley worked on C3, but as modularity itself would require an architecture change it's logical that this will be a feature that will fall into C3s USPs.
Which'll be great, because it has a real shot of turning what could be a slow start (as any new version of software would have) into a community supported one.