What about 9.O-O?
dxc3 seems to win another pawn with no compensation.
How about 5. Be7?
Idunno. I think 9.O-O is playable.
5. Be7 is surely the best move, but the point of taking the knight first is that after 6... c5 7.d4 is no longer possible and black will have stronger center.
10.Kmoves looks possible.
IMO 5...Bc5! is still the most accurate.