fzr cams would improve things, id imagine stiffer springs would be needed too....
the whole carbs thing as far as im aware hasn't been looked at that much and jetting hasn't ever found a good balance without adding big flatspots, i suppose adding fzr cams, pod filter or similar high flowing filter slightly larger jets and it may well run so much better...
problem being fzr cams are around £90 (fzs are £10-£15) then springs, + jets and filters then youre going to need a dyno...
i will do some research and post back..