I mainly hope for only simple potency adjustment, and maybe a slight damage buff on your targets affected by thunder or aoe thunder. Best thing would also be to allow instant cast when swapping from AF3 to UI3, and the same for the opposite. It would make Fire/Blizzard 3 instant in the rotation and would allow for more movement/weaving tools. And maybe some cooldown reduction on leylines, like going to 60sec.

This is all that I can think of, the job is kinda perfect right now and I suspect we will see a massive BLM rework soon in 6.0 or 7.0 because otherwise it will just reach a "MNK" point, where every action added does more or less the same thing and is kinda useless.