The kernel itself should not be tied to a specific ROM, although I am not sure about taking it to Froyo. You can try to play with the files and see if you get it working. In any case I hope to have time soon to start looking at Froyo myself.
Regarding the modules, like I said I will take it under consideration for future releases and try to keep the modules that load with =y to a minimum.
I do think the frequency table should not be too large, I tried to include enough frequencies to suit everyone's needs but not too much.
Finally regarding the dalvik2sd, if it bothers you, use this update to disable it: