What abilities need to be on my main hotbar(s)? Which are abilites do you use the MOST? Which do you need quick access to for those "oh ___" moments?

As I'm leveling (slowly) I would like to form GOOD habits, so when I start raiding I don't have to make too many changes in the way I play the game. I would like to do some raid progression, but not necessarily the very top tier. Right now there are abilties I can bury because I don't use them often, but I expect I'll need later. For example: I almost never use raise, but I'm guesssing I will need to use that in battle later in the game? Obviously the abilities I use most need to be on my main hotbar, but I've also noticed things I don't use often, but need quickly accessible on demand (Potions).