My bias:
I've almost always played Alliance; I have a lowbie horde alt on Firetree that I haven't played in ~2-3 years (or more?), and thus my memory of Horde cities is weak. I've never seen an assault on a city boss, so I could be talking out of my ass for most of this.
General Concerns:
In order to kill a city boss, we must:
- have enough of a raid for both damage and healer longevity
- mitigate/avoid special attacks
- be able to either avoid or fend off the onslaught of enemy players. (This is, I believe, the harder part.)
- fight in-town, to avoid leashing
World Bosses
Starred bosses are the ones you can get achievements for.
Alliance
* King Varian Wrynn (Stormwind)
* Tyrande Whisperwind (Darnassus)
* Magni Bronzebeard (Ironforge)
* Velen (Exodar)
and
High Tinker Mekkatorque (Ironforge)
Arch Druid Fandral Staghelm (Darnassus)
Jaina Proudmoore (Theramore)
Of these, the best ones IMO are in Darnassus. Fandral is a dick, and I bet nearly the entire town would cheer you on for ventilating his spleen. Moreover, his tower has only one entrance, so you can guard it more easily from PvP, I expect. Tyrande is in a temple, and you can I belive fight her on the second floor. Similarly, the Exodar has several raised platforms that could probably be well defended... though I bet there are lots of guards nearby.
Horde
* Thrall (Ogrimmar)
* Sylvanas (Undercity)
* Cairne (Thunder Bluff)
* Lor'themar Theron
and
... others? I don't know who they'd be, aside from Varimathras.
Sylvanas looks like a relatively tactically sound fight -- single entrance, etc, and around the outer ring of Undercity, which is less populated (and has a back entrance).
Cairne looks rough; he's very centrally located. Perhaps moving the fight underground where the forsaken hideout is would be a good idea -- I seem to recall that being off the beaten path.
Theron is, apparently, best fought in the "inner sanctum". I can't comment on defensibility vs players, though.
Thrall is, of course, the Big Man. You might be able to fight him in his throne room, but you might have better luck moving the fight elsewhere to the Valley of Honor, for example. This way, your pvp-defenders can be far enough from your kill team that you're unlikely to get seeds/aoes/etc inside the fight.
.... I'm lazying out, now.




