The tree, without dual xbow, is very competitive. I’d argue to the level of mechanic if not more, specially on a universal prestige class.
Now, add the dual Xbow insanity. There is no way to balance that, the whole idea is borked. Attack rate for ranged was never balanced around x2 sources.
Worst part? They could have released inq without the two xbows silly thing and it would have been something like vistani.
https://m.youtube.com/watch?v=HiGisrw6SX0
https://m.youtube.com/watch?v=HiGisrw6SX0
https://m.youtube.com/watch?v=DNaRU0GiMR0
My balancing suggestions is to simply delete dual shooter and add, if you must, some alacrity bonus there. Anything short of that is a slap to the face of balance. Aside from the visual and mental insult the two xbows represent. Not only is ugly, physically dubious, but also glitches to death in many instances.
Honestly, it looks and feels like someone unlocked the cheat code for ddo; it is that bad. Paywalling it is just making it a cash grab on top of the other things.