BLM or BRD

[Ringabell]

If we're talking about fun factor?
BRD by far. The mobility and constant pew-pewing keeps you on your toes. That is more interesting to me than BLM which (as some people have described) is more like a turret.
Also I find the BLM rotation quite boring, but that's just me.

Both have very good AoE damage and very good burst damage. Good BRDs are in higher demand than good BLMs (sad but true).

You will need cross-class skills from ARC/BRD if you go BLM but not vice versa so you may want to factor that in as well. Quelling strikes is unlocked at the fairly high level of 34 so...I'd say level Archer and if you like it at 34 keep it, if you don't, switch to BLM and you'll be all set.

I wouldn't put them in the same category for AOE & Burst. BLM has far better AOE damage and far better burst damage. BRD is higher overall because once you start to move my poor BLMs DPS drops significantly while the BRD doesn't miss a beat.

I agree that BRDs are in higher demand as they're generally better suited for maintaining higher coil DPS AND they support the group.