I'll have to agree with the "Against C3" people - as already mentioned there's a mountain of excellent tools, probably spearheaded by Unity and Unreal engine for "serious" development. C2 provides excellent tools for fast prototyping and making products that fit its target platform - HTML5.
All the people asking for 3D and built-in isometric engines and what not so very often honestly feels a little ridiculous - if you need that just switch to a different engine. C2 has been very open about what's possible and what's the expected output.
As for performance - mobile devices have basically already reached the pinnacle of resolution - there's no point to go beyond 300 dpi, the human eye simply won't see the difference. So you won't have to go beyond Full HD in the next year or next 20 years - the human eyes won't magically improve (well, probably). Devices currently coming out easily work with that resolution at a decent pace and they won't slow down - which means that as the time goes on your limits will stay the same, but device power and support will only improve enabling A LOT more to be achieved. Not to mention desktop PCs which are already beasts and will, obviously, also continue to improve.
I for one hope that C2 continues improving, gaining new useful functions and as time goes by HTML5 export to mobile platforms improves as well to eventually reach that desired "One click" stage.
What I want in C2 for 2015 is simple - random values in object parameters - so, for example, you put random(360) in angle inside the editor and every time the object is spawned it has a random angle - would make event lists so much cleaner.
Switch to other game engine like appgamekit2? Apk2 has a 3D engine and supports blendergameengine, but it is very difficult to handle. I guess that C2 is the easiest game engine. How difficult is scripting? Leadwerks and unity are easy to learn?