Pick an element to go with (Fire/Physical is good for DH).
Craft new bracers with +element damage on and craft new shoulders - the rolls are low and at this point you dont really need +skill dmg (especially spike trap...) same goes for pants and belt.
Get a socket in your weapon, an emerald will boost your DPS significantly.
Your armour needs replacing, one socket isn't good enough, try to craft a new one with at least Dex and Vit, if you can AR/Elite damage and then roll for sockets (armour isn't as important due to 2.1).
Farm A1 bounties to get the Ring of Royal Grandeur (lowers set requirements by one).
As for skills, get rid of ambush, it's really not helping at all - you'll get an enemy down to 75% health... then? The passive is useless.
http://us.battle.net/d3/en/calculator/demon-hunter#aQdVOS!bXfh!ZccZYb
Try something like that, its far from perfect but you should find that it works a lot better. If you still feel squishy, change the rocket passive to awareness until 2.1. Note that not all of the skills are Phy/Fire - some need to serve as utility/provide better build synergy. You could swap out Vault for Smoke Screen (Displacement) for CC immunity.