After 50 hours I beat every boss and encounter in the game completely solo. No ash summons, no NPCs, just my own raw skill. It wasn’t actually that hard besides a few parts toward endgame. Malenia killed me 30 times with that cheap one-shot spam attack. And Mohg was difficult for a while until I switched to a bleed katana.
Overall I give the game a 8/10. The open world is tedious after the first playthrough but the legacy dungeons and bosses make up for it.