It may be down to my advancing years but There do seem to be a lot of abilities jumping onto my action bars or abilities book which seem to be very similar.
I've managed so far (24) as Ranger/Marksman/Bard making the choices as I level and I still seem to do the same few abilities each fight changing according to circumstances, opponents, adds etc. I'm probably doing it all wrong but I manage to stay alive quite often and enjoy the game.
However last night I bought another role since my early time playing Warhammer (tabletop, not MMO) had me hankering after BladeDancer. So I duly set up the role as BladeDancer/Riftstalker/Mad Arsonist and dumped most of my points into Bladedancer.
I had abilities dropping all over the place and unlike the ranger, where they arrived one or two at a time, I have no feel whatsoever for how to play the character or what works better. And many are confusingly conditional - they only work for 10s after another ability - or only on Tuesdays if it isn't raining. I sat for some time reading all the text and came away no less confused. I went and mistreated a few L18 mobs to try stuff and was no less confused.
Personally I think I'm going to have to start a new rogue character and level through the acquisition of these skills before I'll have a clue as to how to use them. There was a much better feel for a new skill when you just got it - by itself - and tried it out, than when 30 arrive at once with no feel for seniority.
I can see why there is so much discussion of rotations or priority chains but its all a bit theorycrafty for me. As someone else said, getting back to the WoW TBC macro-mashing isn't a recipe for enjoying the game.