-Raids are too micromanaged. What do I mean by that? Restricting potion usage. Restricting battle res. You limit choices for raids. Yes, it needs to be done to control the race for world firsts, but it also hurts the fun of guilds not in the world first race.
For one, I do not miss - not even for an *instant* - having to have 4 flasks, 2 stacks of Strength pots, 2 stacks of Agility pots, 2 stacks of Armor pots... and the absolutely, stupidly, ridiculous amount of time and effort it takes to maintain that on a 3~4 day/week raiding schedule.
The battle rez's, and replication of raid buffs & debuffs is a result of Blizz having to make concessions for 10 man raiding: There was plenty of room to get whatever you needed in a 40 man. Raid comp was a little more limited in 25's, but not too badly. But with the rise of 10's, the old~style ability spread led to aggressive guilds having set comps, and rotating players in/out of the raid based solely on whether something was perceived as "needed" for a particular boss.
For obvious reasons
(i.e. - it fucking sucks to have to park/sit outside while your guildies are raiding... just in case they decide they need "[Curse of Elements]" or whatever your class brought. And it *really* fucking sucks to be valued sole~ly on one debuff). So players (Rightly!!) complained that Blizz needed to make buffs/debuffs more widely available (done), and do a much better job of balancing abilities/DPS (work in progress, and always will be).
-PvP gear. In vanilla Wow, you had one set of gear and that was it. You could use it to PvP or PvE. The requirements to constantly PvP to get PvP specific gear limits the fun for people looking to do battlegrounds just once in a while. It takes too much effort if you're going to need to grind a whole new set of gear just to do some BGs a few times a week.
I kind of agree: The original idea was that PvP gear would be one of the tools Blizzard could use to balance classes. This has been... less than successful. The only response from Blizz on this is a pretty weak
"Well... casual players can stay out of Arenas and Rated Battlegrounds, and work together to achieve a more even footing with the more dedicated PvP.. blah blah blah... Weak...
But that falls far short of the real issue: That PvE and PvP are essentially two completely different games. IMHO, it won't be possible to balance it unless Blizz did a DOTA~type deal where you may choose premade toons with pre~assigned gear, leaving nothing on common with PvE. i.e. - Acknowledge it's really two different games, and codify it.
-Lack of community. This is the biggest issue. Random Heroics, flying mounts, insta teleport dungeons, and phasing has basically eliminated the sense of community in wow. You will almost never meet anyone else in the world unless the zone is a daily grind spot.
I totally see where you're coming from on this. Just that the current system was created so players didn't have to spam Trade/general chat looking for groups. But, of course, now that the servers are matching roles for dungeons - the chances have been you would never run into people from the same server. Therefore you lose social controls on behavior, and LFD becomes
"The Place Where You Can Be An Asshat With No Penalty". Whereas before, you had social recourse
("I know your Guildmaster..."), and bad acts could come back around.
It's gotten a little bit better since Blizzard changed the priority system to match players from the same server, if possible. But still...
The other thing they were trying to solve was Tank/Healer imbalance. The theory being that DD's had a larger potential pool of Tanks/Healers, and therefore queue times would improve. Well... Not so much: I still only do dungeons in~guild
(2 Tanks - Protwar and DK). And even with the little carrot of an extra reward, I'll only queue randoms if/when I decided I need to cap on Valor and will come up short. That happens on my DK, but now that we're clearing Firelands it no longer happens on my ProtWar.
Many of the other Raiding tanks I know do the same thing - only queuing when they need the VP, and out of guild only when guildies aren't available.
The only time I directly queue for randoms is on one of my DD alts (Warlock, Hunter...). So I don't believe the dungeon system does much to "solve" the tank/Healer issue. Certainly not for players who raid regularly, anyhow.