I’d say say Semin has the better peak in the regular season. His ‘09 and ‘10 seasons were awesome, and the only one Kuznetsov had that was close was ‘16 where he was 9th in scoring without top PP time. Kuznetsov had more good, reasonably healthy seasons though. Kuznetsov’s ‘18 run was the best in the playoffs between the two though, and arguably a better peak than Semin. I guess it comes down to what you value but I’d argue Kuz’s playoff run is probably too small of a sample to argue for “better” player