Welcome to the healer role!

Unfortunately it is exactly as you described it. AST changes made the job absolutely un-fun and that's exactly why healers complain so much. Unless you prefer fast casting job, I'd suggest switching to WHM to at least enjoy the blood lily. Or max AST and see how it feels at 80 but it's dynamics don't really change much.

Personally, I decided to completely ignore the seals in roulettes/alliance raids. Everyone gets whatever I draw and everyone gets divination when it's up. It didn't made the job more fun but it removed a portion of my frustration with it.

Hopefully changes in 6.0 but until then, it is what it is.