Maemo is a multitasking os while nitdroid only does one thing and maemo uses the X-window system, while android doesnt even have X...

The hardware should be capable, the problem usually is how the software is written.
Just compare the difference in speed between the maemo browser and firefox. Since both are based on the same code they do roughly the same thing, but the huge difference in speed is because the maemo browser has been compiled by some clever people.

-If speedpatch is a part of the problem, then Speedpatch probably needs some tweaking