Just got the Platinum for Nioh. I found it really enjoyable. The combat is great and I quite liked the quirky onmyo and ninjutsu powers. The levels too were quite good, with some great locations. I wish each zone had different side area locations. I was disappointing with seeing the grassy area again in a different zone/island. I also wish there was a proper story mission on the river Sanzu just because that side mission area looks great and I'm sure they could do interesting things with it. Loved the Mt Hiei, bamboo mountain and the foggy level with the Ogress.
The enemy variety as has been pointed out, is limited, but it did mean I could rinse through the harder later levels at much lower levels and barely ever get hit. Not with the Karasu Tengu though..
Bosses were fun and enjoyable, particularly the yokai bosses. Orochi felt like a dps race though, which was not great.
I will definitely be looking forward to the DLC.