BLM here since 1.0 and I have to say I have not really had an issue with movement heavy fights. Ultimate is pretty easy when you know the adds are coming. just make sure your Astral Fire III is active, swiftcast Flare on the first set of adds, convert and switch between Blizzard III and Fire III since its a 1 second cast. Use Scathe while dodging lasers, (seems to crit for 500 quite often on my character).
As for Haukke HM, memorizing the floor AOE patterns is very simple. Know and anticipate when they will come, move to correct location and continue casting. That's a pretty easy fight and for a geared BLM who knows the AOE rotation, its fun and he goes down very fast.
Same thing goes for anything else really, if you're on the run, you can alternate between Fire III and Blizzard III. Sure you deal less damage while moving, point is you're still casting and staying on the DPS meters.
The BLM isn't just a "stand ancd cast" class. There are numerous mechanics at your disposal to prevent you losing full DPS in an instance.
Did I mention manawall for Titan HM/EX punches? Don't need to move for 2 hits. Cast again when the CD timer is up and its no problem :)
I could go on and on about what you can do but if you wanna play the BLM, you gotta figure the character out and play it to your liking and whats easiest for you, and most beneficial for the team.
