I would actually rate the game an A. It's one of my favorites from the PSN. I do agree with your cons somewhat, but they didn't overpower the pros for me. I've actually replayed the game multiple times, just because I love experiencing it even if I know how to solve the puzzles, plus it's fun to speed-run. There are also unlockables earned like rapid fire shooting which really helps for those vine levels which can be a slow slog as you mentioned. Glad more people are getting to play through since it was on PS Plus. I think it's a real hidden gem.

_________________