So far, it sounds like I will like it.
The offspec thing is going to be an issue unless something like one of the previously mentioned ideas is implemented but it seem like otherwise much whining can be avoided. My guild does partial LFR runs now that I refuse to go with them on because they do the whole "all need then distribute" thing and I think that's jacked up. I don't like it when others do it and don't want to be part of it. Plus, if I won something and was told to give it to somebody else I'd just be pissed and we don't need that.
I like the shift from needing Valor to gear out, to drops being actually usable. I can't remember the last time I kept a dungeon drop on most of my semi-geared toons. It seems you don't really run dungeons anymore in hopes of loot because the Valor stuff is better - and even then it's tough to invest too much into that because you can probably run LFR by that point which makes even most the Valor stuff obsolete. LFR takes about as much time as a dungeon (maybe 2), provides way better stuff, AND gives more Valor. Dungeons have become nearly obsolete in that sense except as a brief stepping stone to LFR, much like "regulars" always have been with heroics. If they can even things out a bit to make more than 1 thing worthwhile, that would be cool. I already raid DS 2 nights/week. Most my other toons qualify for LFR so if I were really interested in gearing them, that's all I'd run. On 7 toons. DS would literally be the only place I'd ever be in game. I've been working on my fresher 85's (and other lowbie alts) just so I can be somewhere other than Dragon Soul.
If they implement that deal where all the drops are from bosses and you can use Valor to boost your current gear that would at least give some incentive to continue running stuff. I'm currently collecting points on my main raid toon that I have no idea what to do with. She is in full 397. We haven't cleared DS yet (although made it 6/8 in one shot last night so high hopes for this week) so we can't do Heroic for 403 gear. I literally have nothing else to get for her. If I didn't have 30+ alts I'd have been bored out of my skull ages ago. BUT, if I could use that dust-collecting Valor to boost my gear up to 400 or 401 or whatever, and others in the group did the same, maybe we'd have been working on Heroic mode already. Maybe 5 Valor = 1 stat point kind of like reforging. Would have to have a cap clearly, but still. It's a neat idea.
The enchanting thing will be an issue too. Mat prices already skyrocketed when mogging came out because people want to buy the gear rather than d/e it. If they eliminate the d/e option in runs as well (via individual looting) that is going to seriously crimp the influx of mats. It sounds like it's just LFR for now, but I guess we'll have to see.
Oh, and aoe looting sounds amazing. I end up running old content quite a bit either for achieves, mounts, pets, profession or whatever and it's obnoxious pulling and 2-shotting an entire instance then spending 15 minutes cleaning up the mess.
After writing all this and thinking on it some, what I'd almost like to see is a system where Valor gear or drops or whatever are BoA rather than BoP, at least up to a point. That would solve a lot of the issues of "my warrior has sharded that axe 12 times now but can't get it to drop for my DK" or my own situation of one toon with a bunch of points and other toons in need of gear. I can buy 1 piece of BoE gear. Yay? Maybe keep whatever heroic-level stuff they have as BoA and raid-level stuff as BoP. At least that way you don't have to do the entire reg>heroic>trolls>HoT grind (or whatever the new equivalent will be) on *every single* character.
in my book. 
