How do you enjoy playing casters?

[LitheSuxman]

I started playing not long ago and played NIN through the entire ARR as soon as I got the job, and intend to keeping it my main. But I think NIN has spoiled me so much in terms of the quick actions and instant button response, with that I find casters horribly annoying to play.

So far I've tried Astrologian (aka the s tier healer), the damage output seems unforgivingly low in low levels that even doing quests is difficult if not also being slow. I've also tried Arcanist (at lv 29 right now) but I'm hesitant to play it any further because of the slow casting. I could only imagine Blackmage's gameplay would be even slower.

In short, idk how to adjust myself to play casters. It's really frustrating especially in group settings when mobs die to someone before you even finish casting. It feels very unrewarding and slow. How should I approach caster job?