Yeah, I think the solo bonus being added into the star cutoff needs to at least be toned down, not necessarily removed altogether. It's totally obnoxious with how large it is right now, and needs to be cut down to at least half, if not lower, to compensate for the large solos for when a single miss is causing you to lose out on 40,000+ points.
I agree with the trill lanes too, there's something off about them. I have a lot of trouble playing in-time with them, and almost always have to play too fast to get them to register, meaning I end up off-beat, and then can't hit transitions. If I can play the same exact things in other songs that don't have the lanes charted, I don't see why the lanes make it so much harder.