Finished my hard mode run today. I think 4 is pretty good but Ryu felt like even more of an afterthought than I already suspected. He basically got the dmc4 Dante treatment but even worse, and then Yakumo with dark dragon blade steals his moveset .
I ended up liking Yakumo's general attitude a lot and his gameplay is great with each weapon having a specific trick to them. Staff ended up being my go-to. The parry/perfect block almost felt random because enemies attack so fast it's not something you really do on reaction, but against bosses they're really good. Getting used to responding with blood/gleam after parry/perfect block is a game changer.
It felt like 70% NG which honestly I'll take at this point. Already a miracle this even exists. Actually looking forward to continuing master ninja on it.
I'll give it a few more replays but as is stands 2>4>3 and 1 is kind of it's own thing.