Piccolo vs. Super Perfect Cell

If current Piccolo could, what about ssj2 cell?

Piccolo annihilates him. He's grown too considerably since those days.

One shots cell. The only keeper up here from DBZ is Buu and possibly Broly and Janemba.

Yep, though if Cell was ever brought back at all he'd no doubt have a shoehorned power increase to become relevant again, but just going by him in Z now, yeah, he'd be nothing to most of the universe 7 fighters at this point.