I'm 858, and WQs are still 830/835. They have to cap somewhere, they aren't meant to be a 100% guarantee'd way to gear up after you hit a certain point (830ish, conveniently the ilvl needed to start mythics/raiding), but due to titanforging ANY loot from a WQ can go up to (currently) 895 I think.
You got 3 pieces of loot, none of them were warforged, and just based on that you assume it's a low chance? When I do 2-3 chest runs(4-6 loots) I almost always see at least 1 upgrade in ilvl per run, and tertiary stats roll like crazy now. I'd say the chances are higher than they were in WoD, or maybe it's just that there's a lot more opportunities to get gear.
How should you progress? Well, keep doing what you already did. If this were WoD, you'd be stuck at ~635 (heroic gear) with pretty much no hope of going beyond that unless you raided, so I'd say the fact that you can get gear from WQs and 5 man dungeons is pretty nice.
Aaaaaaaalso, You have time to run M+, but not 5 minutes to throw a group up in the finder when you get a keystone yourself? Literally, if you have a keystone, you can get a full group in less than 5 minutes. Or you can even give your keystone to a carry group.