... though if you're just starting the Quest dungeons, you won't be seeing a 3rd-level Limit Break any time soon.

The thing you should know early on is that your limit is shared with Archers. If either of you trips a limit, you get an AOE heal effect. Chances are the limit breaks are mostly going to be used by non-healers in your dungeons. If you're finding you have to LB constantly, double-check your play style. If you're tight, but still having trouble.. try befriending some good tanks on your server instead of always being at the mercy of whatever slop Duty Finder throws your way.