How I would do a sequel
If I could have a Baskhi helmed sequel combined with what I would like to see, here is how the outline would go.....
Goal--to create a movie that captures the feel of the original, but not be the same movie. Obviously 80 years have not passed since the original but it's plausible Pete could have young adult children by now. Also the original is about the rise, fall, and redemption of this family over said 80 years. Sequel would be focusing on what Pete does with this fame to make the first movie a vindication of all their suffering.
So Pete's career was hot into the 80's, his music got harder and more metal oriented, but by the 90's it's basically over. He rides out the lurch because he's rich, and thus really won't acknowledge he's not the act he was in 1989. In this part you could work in things like grunge music bringing the end of metal, as well as the hair metal/arena rock scene that immidiatley preceded it.
By 2012 his soul source of celebrity comes from being a known name, kitch factor, and his contemplating a reality show based around him. He crashes hard emotionally though when he realizes what that means---he can't make money on his art anymore, just on celebrity.
On the personal side he's had one or two kids---he hasn't been an absentee father, he actually was a part of their lives, probably because he himself lacked a family. I would guess he would overcompensate for his childhood poverty by spoiling them.
The film would revolve around some confilct and reconiliation with them that would kind of tie the last loose ends from the first movie up---they got their fame, but they never became functional, healthy human beings emotionally. In this one they could.
Not sure what the issue with the kids would be, but maybe he wants the kid to pursue music and fame but the kid would rather be a lawyer or some other normal upper middle class, non artistic pursuit. Prehaps Pete could have a step-kid who DOES want to be famous, and has the talent and drive and he's blinded by that.
Just some ideas I had.