I'd be fairly surprised if bows become meta even so lol. But fair
I don't think Ameliorating Strike was ever on-hit? There was a period on Lama when it was "when your smite crits" but that was changed when it went live in 2013 (
link). It's still nice, and better now that Smite has a 12s CD, but it would possibly be the strongest enhancement in DDO if it was on-hit lol. If you're looking for party support it's also pretty handy as an AoE heal that doesn't slow your DPS down.
10% Doubleshot is nice from Warpriest T4, and Magical Backlash from T3 is surprisingly helpful when fighting casters (whenever there's >1 and they get to cast, it's knocking someone down with no effort on your part). Still, yeah, it's a harder sell spending >20 AP there vs like grabbing more AA stuff (more dice, more DC's, Paralyzing, etc).
If you're looking for party support I'd recommend against terror arrows. In certain niches they're good (soloing, all-ranged DPS party, probably something else too) but most of the time you're just chasing mobs away from your melees and out of range of your spellcasters, which is pretty frustrating for everyone involved. A lot of people will ask you to not use them, myself included. There are few things more annoying than having to chase and single-target literally every mob lol, especially now in the golden age of AoE. By all means roll up a test toon (vet 7 works great) and try it, but I think you'll agree.
If you're not just in for Terror Arrows, AA T4 gets a lot more desirable (+2 damage dice w/scaling, +2 DC's, Paralyzing option, etc). And then you're nearly back where we started, 39 DWS/24 AA = 17 leftover AP lol.