My comments are focused on endgame. Since heroic content goes by so quickly, there's little reason to optimize for it. And if you're only doing heroic lives, there are better choices for racial or Ranger past lives.
Scion of Arborea < Scion of the Ethereal Plane for ranged and TWF. Math wise, Arborea only comes out ahead for THF.
I consider Spring Attack to be be essential since Ranger has no native movement speed bonuses. Mobility for ranged is an important defense.
Arcane Archer just isn't good enough to justify spending 41 points in it, especially since this build doesn't have the WIS to make the specialty shots like Banishing/Smiting work reliably in reaper. I'd spend 41+ in DWS, and get AA Metalline Bypass (core 3). Unlimited SA range is powerful, and you'll have 12d6 SA between DWS and Ethereal, 45 from Deception and 3 from rogue past lives. Another 6d6 if you choose Shadowdancer, 3d6 more with Halfling (more optimal than Scourge), and 3d6 from Artifact. 24d6+48 sneak attack damage from any distance is amazing because it scales 150% with Ranged Power. That's 198 sneak attack damage before RP scaling. Reliable SA damage > acid arrows. It also frees up two gear slots, which you can use for LGS 2pc Opposition. That's especially important if you don't yet have enough reaper points/PLs/HP from getting one shot.
Select FE based on the most difficult content. FE: Fey is obviously missing. I wouldn't ever select FE: Animal as a Ranger feat. For 2 AP, it's available in Falconry. With the resurgence of LOB/MA, I would absolutely select FE: Construct. Also, plenty of constructs in Sharn content. I'd also highly consider FE: Plant.
I wouldn't bother with Alignment Bypass (core 4) -- slot an augment in a spare Twisted Willow if it's really needed. That frees up plenty of AP to dip into Falconry for FE: Animal, FE in T5 DWS and an easy 60 HP in DWS. I'd also pick up Deflect Arrows from 6 AP in VKF, along with FE: Undead so you can go Halfling, and 4 in Tempest for 2 second Deflect Arrows. Archers and spells are what's going to kill you.
You don't have a Spellcraft +19 augment slotted.
The Celestial Sapphire Ring is a wasted slot. You don't need to slot Improved Deception thanks to Sniper Shot, and 21 INT provides an underwhelming 10 Spellpower. If you really want INT, you can craft it on the Wildwood Wrists or slot a +12 INT augment. You can also slot Profane now, not that it's required for a ranged build since you aren't building for DCs. Ring of Prowess will net you +8 RP, more if you have a mythic or reaper version.
I'd prioritize Shattered Device 4pc if you're glued to the acid arrow concept, since it's both PRR and MRR reduction. And your Alchemist will thank you too. Even without acid arrows, I'd slot 4pc Shattered Device.
Even with these changes, I still wouldn't play a bow-focused build until the bow revamp is released. Bows are great 16.6% of the time, and terribad 83.3% of the time. If you want ranged, throwers are the optimal choice today.