Flamethrower is a joke, I stay away from it's use. In general, I feel that we bounty hunters already rely on too many abilities that cause us to channel for far too long. Like, I love Death from Above, but the casting time is so ridiculously slow I find it frustrating to use in PvP...you've got to channel it, you've got to have the right distance, you can't move while casting, enemy players can dodge it with ease if they havent already done so inadvertently, AND it's easily interruptible. Concussion missle would be great set up for it, but it's also way too slow to cast, which leaves electro dart, but players break out of that easily enough.
Anyway, even some of the heals require us to stand still, too much rooting!!