Galatic Challenges are a real time sink. Especially when you have no idea if you're even doing anything to achieve hidden feats. I really don't enjoy it.
Raids on sims I don't think saves much time (for end game players). There are periods where there's a lot of reliance on particular players in raids...........then it's a real chore. When you're past that though, it's basically putting it on auto and getting somewhere.
I find overall it blows hot and cold. Some times you have too much to do, other times I log on and I'm looking in bushes and under logs for things to do.