I love TAS. It's actually my earliest
It was actually the thing that I watched the most of Classic Trek wise when it aired in the UK in the mid 90s. Other than that I was always just the films and TNG onwards. I know the studios don't consider it canon, but I've wondered how much was actually contradicted. I read one of IDW's TOS series and they had Arex in it, and I loved that TAS put two very alien looking characters on the bridge, even if one of those was a cat lady.
Yesteryear was also brilliant.