Northstar is not impressive even in long fights
Look at Northstar 7 star R1 vs Kate R4a, even with class advantage he takes longer than Kate to finish. Mind you Northstar has 4.5/5 damage whereas Kate has 2.5/5 damage rating. Not mentioning Kate is better for small and medium fights as well.
If they had to make Northstar an Everest champ they should have made him even more op. He feels too slow, more than what his fight duration because of his weird animations taking an eternity to finish. Hope they buff him to match his damage rating.