"And so with the evil shadow" ...
I think equipping an item consistently makes the game crash, no big deal once you're aware of it.
The game is very fun. Every single monster looks super cool and given the context I think they're very elaborate which is quite a feat as they're also plenty of them. The soundtrack is great too. I like that with the right element a monster basically dies in one hit, I had plenty of fun making full use of the right elements, competely switching to a different full team of the same good element for each dungeon.
My only caveat that I'm mentioning only because the game is overall great would be that the trees, rocks, etc.. feel like they're built 16x16 and then resized to 32x32 which feels both a bit too big at all compared to the most traditional NES games so in the end the game doesn't completely look like those and also inconsistent with the characters on the map. No biggie, especially as once again the monsters during fights look amazing.