I am a sucker for Standard, as in "less cards to keep track of, more diversity once rotations happen", but then again, I just recently got back into it (:
It's definitely simpler! And I think it's also easier to have success with home-brewed decks, whereas in eternal it feels like you need to play with a hyper-optimized deck especially in higher ranks.
I lean more towards eternal for the higher power level and because there are more cards that I like. Also I don't play that much so I have to keep up less with new cards if I play eternal