Zul'Farrak was one of my favourite dungeons in Vanilla and it was fun to revisit it. It just has it all: a straightforward layout, easy access from a zone in which you'll spend a lot of time questing, a whole bunch of dungeon quests, lots of bosses with great drops and an interesting setup. The stairs event worked great. The only issue I've had, every time, is with Witch Doctor Zum'rah. I remember back in Vanilla, the very first rule I was taught the first time I did this dungeon and got close to this guy was "DO NOT TOUCH THE GRAVES". When we came back later, at a higher level, we would loot them for fun and AoE the zombies that spawned, but in general it was accepted custom to leave them alone. I can't recall the boss himself ever giving us any trouble - yes, he spawned a bunch of adds, but they weren't too bad.
Yet every time I've run this dungeon on Kronos, the witch doctor is easily the hardest fight in the entire instance. I've repeatedly wiped on this guy. He summons zombies really quickly and they hit like absolute trucks. Some groups I've been in have tried to avoid the issue by emptying every single grave beforehand (which seemed outright bizarre to me, considering the seriousness with which the "do not touch the graves" lesson was driven home back in the day), which does seem to help but takes up loads of time (and since the zombies hit so hard, the healer needs to drink pretty much every other pull). I don't know what exactly is wrong with the fight, but I do know that this is not how things went down in Vanilla.
Actual Vanilla screenie from when we did decide to open the graves.If Zul'Farrak is one of my old favourites, Uldaman is the exact opposite. I remember really disliking that place back in the day. With no map view for dungeons back then I tended to get lost all the time, though this is significantly less of a problem ten years later with me being quite familiar with the general layout by now. The intended level range of 38-53 was also a terrible idea, as it meant that you either got no XP for half the dungeon or would run into a massive brick wall towards the end of the instance. Oh, and of course you had to go back there again and again due to the way the different quests were designed and the fact that enchanters were looking to visit their trainer. (I'm still baffled that anyone thought that putting a profession trainer inside an instance would be a good idea!)
Grimlok didn't shout: "Me Grimlok King!" The last boss, Archaedas, has remained in my memory as the first truly involved dungeon boss fight I ever encountered, as he spawns multiple sets of adds that need to be controlled. I also recall him summoning a copy of himself near the end (or something like that) which didn't happen in this version and made me doubt my memory a little. We wiped the first time anyway, which caused our tank to pull him out of the room the next time. (Again I found myself hesitant: Shouldn't those doors lock when you engage him?) This completely circumvented the add spawn and turned him into a simple tank and spank, which was slightly disappointing but also intriguing.
"Only" ten more levels to go...