Yes but the "futur" support for using well HTML5 app with similar native perf could be very very long.
I prefer to have a solution that is limited but trully small and efficient for doing what 99% of users do with Construct2 : Mobile Game.
i don't need ajax, json ect.....
Just to draw the sprite, audio support, save some data (the way you want), input, and the way to lunch some link for external social support + ads.
Don't need a perfect web object support ect...
I prefer a solution that is veyr fast and very tiny for mobile game with some limitation vs a heavy and slow solution.
PS: test the demo Tsunami Cruiser run with sound at 60 fps without any problem.
PS2 : yes a 10K sprite demo is nothing without game engine pipeline sound ect.. jsut a testing for wrapping api but a good test to start.
Did you test also Ejecta V8 Engine :
Perf are really good too (better that basic browser (chrome last version on android not too bad)).