So, I completed Balor and every single quest there besides the one that requires me to go inside the raid (six of them). I'm a Horde druid.
1 The single graveyard in the zone is awful. It's on the main island, and I can see why it would be convenient when you do quests there, but there are four or more other islands besides it. The SI:7 (or was it SI:6?) rogue NPCs that stealthily hide to ambush you on the starting island have a high chance of killing you.
2 The quest givers rush out of their way to attack those very agents when they appear at the top. It shouldn't matter to people who just click and accept the quests, but if you were planning on reading the edgy Kilrogg lore (and it was pretty interesting), you're going to struggle when he’ll rush away to slam his fist at the intruders.
3 The main island is very small. I can’t imagine it supporting twice the population doing it.
4 There was an issue with the ship where it phased out of reality like Borealis. Both mobs and players appeared and disappeared in front of my eyes, and I was told it was not a phasing issue.
5 I’m a druid, so swimming wasn’t much of an issue for me, but it's probably annoying for everyone else (maybe not a shaman). The quest that asks you to kill two elites under the water is horrible, underwater fighting isn't it.
6 At one point in the image attached, the bridge was sunk too low into the ground.