SMN is the least changed. You do have to "keep track" of Aethertrails, but really it's not all that hard to space out your Aetherflow uses unless you're the kind of person that sees you have it and must use it asap.

WM is meant to be kept on as much as feasible. The 30% damage across the board plus Empy is just too much to be losing out on by toggling.

Can't speak for BLM as I haven't leveled it to 60 yet.