I have the particles bug too, but I didn't try the minimal mode, i just don't have any particles from my first run (I didn't change anything, it was premium all along).
Btw I tried as-steep. Well in the one hand, it's great. It makes the boring songs interesting, not harder, but much more interesting, and it's good this way. But, on the other hand, it makes the faster, and thus interesting song somehow dull. They still fast, but the layout of the track gets much smoother, there's no steep curves, bumby tracks, it's just fast, and it's not too good this way.
So it would be better that if as-steep ever got to be the default algorythm, it would only apply to the songs with traffic lower than (about) 150, and the old algorythm would do the work for the faster songs.