Don't use ajax request, use web sockets.
Thats in my plan 
Nice project. I think, it is better to try mining Scrypts with Khs. That would benefit you and your users. GooD Luck
Thnx!Also, I just put a settings button.
Now can reach 1 mH/s
Still small and can't get you any bitcoins but this is still a funny little project.