Before anyone asks - yes there are archived copies of old addon versions both on our github repository and on several of the addon sites we use, and these will continue to be available after Cataclysm comes out, so you'll be able to get those old files if you really want them. I'm not going to bother making these more easily accessible unless you give me a very good reason. "I'm on a private server and I need them since we didn't upgrade to Cataclysm" is a BAD reason - and it's illegal.
As for the classes themselves, they almost all play like slower and slightly less interesting versions of their Legion counterparts. This is thanks in large part to the loss of one ability from each class that came along with Legion’s own AP dumping system: the artifact weapon, which added a unique ability to every spec in the game. The loss of these abilities left most classes feeling frustrating and incomplete, and though Azerite gear was supposed to be the replacement, it missed the mark completely. There will always be one Azerite trait that reigns supreme for each spec, meaning that the frustration of that particular loop will be unavoidable as long as the system is in the game.
Battle for Azeroth also includes a new legendary neck piece called the Heart of Azeroth. This neck piece will allow players to unlock new abilities that are directly tied to their armor. This system sounds very similar to the one that Blizzard implemented in Legion that allowed players to build upon existing weapons via in-game artifacts. Finally, Battle for Azeroth will raise the current level cap to 120 and will include a feature that allows players to buy a boost up to level 110 should they wish to do so. We can't wait to see who hits the new cap first. 
This leaves players chasing an endless loop of trying to get higher level Azerite gear — which can only reliably be gained through raids and isn’t available in Mythic+ — but only the pieces with exactly the right traits will actually be an upgrade. It’s even possible that some items that should be huge upgrades are nullified by the loss of a specific trait that makes one ability do more damage than the others.

Jewelcrafting is a crafting profession that revolves around gems. You prospect various ores turning them into gems and cut the gems. The cut gems can be added to socketed items. In addition you can craft rings that can either be disenchanted or sold as gearr. The Legion epic and rare gems and rings all sell very well. The jewelcrafting panther mounts are the best old world recipes.
Similar items to peacebloom that are profitable on most servers for people getting started include: Hypnotic dust, Celestial Essences, Relics of Ulduar (and other rep items), and heavenly shards. The same can be said with the earlier wrath enchanting mats, they are still valuable for casual players or those without a lot of disposable income! This list is not the end all be all of making quick money! Check your scan results daily and add to this list and you will be on your way to hitting the gold cap much faster than those who quest or farm!
Once you have your potions, proceed to complete all the bonus objectives in your starting zone. This should easily level you to 92, where you can proceed to Gorgrond. Interesting enough, for some reason many Gorgrond quests are worth nearly double the experience of quests in other zones. Maybe this is a bug, maybe intended, I'm not sure. But I actually recommend you do all the quests and bonus objectives in Gorgrond. For your outpost choice, I recommend choosing the Gladiators, since they give access to more treasures than the shredder IMO.
Was doing it at 52 on my lightforged paladin and it was easily the slowest zone out of the ones I'd done. Granted, I didn't have War Mode on so I didn't have any PVP talents, but it felt like about 40% of my time was spent waiting around for respawns or wandering around looking for mobs to kill to get a quest item that had like a 5% drop rate. Maybe I just got unlucky but I definitely won't be going to that zone again for future heritage armor runs.

If there would be a transmog server #1, all transmog vendors would transfer there and the market would get destroyed fairly quick. In general, Roleplay-Servers like Argent Dawn or The Aldor are better server for selling transmog. On high pop servers you have a lot of other players selling stuff and as a result, low prices. On low pop servers prices are acceptable, but you have no buyers. So there is not recommendation for a server really. Its up to you.
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