There's a lot of straight and level time in both but Airlift has more events / missions that are AP off and can be challenging (Low level, NVG, Assult strip, Airdrop, etc..).
Tanker has some events that are require some of that pilot shit (Min Interval TOs, AP off AR, Formation, IP demos, etc...) but there is more time in the Flight Levels with the AP on.
Blessed and lucky, got to fly both over my career, Tanker was my first assignment and I enjoyed it and later in the ANG got to do Airlift enjoyed it too, I'm back at a Tanker wing now and still enjoy it.
Good trips in both and crappy trips in both and it is even with me as to which I would recommend. Saw more places you would want to go to in the tanker (Pacific, Europe, Canada) dragging fighters / bombers occasionally though.
Both communities have their quirks, about equal on what I found good / annoying.
Everything is what you make of it. Good luck.