It's a no-no, you think you'll play your character
It's likely to be a lot better with TBC and more zones but when it was the classic game PvP, open-world and leveling was a complete nightmare for Alliance players on WOW TBC Classic Gold PVP servers. With the horde-vs-horde queues, there is no reason for meta players (majority of players, not the majority of players) to join Alliance.
It's an outright disrespect to my time, after having spent many hours playing the alliance characters on a server. It is well known that this will escalate into horde dominance of the entire pvp realm. It is not possible to form alliances in open world. It's evident from the classicwow subreddits' response. Wow is a lost cause and the playerbase is total garbage. Players and developers are changing classics into retail gg.
It's a no-no, you think you'll play your character for a while in Classic but you'll never particularly if you've already cleared Naxxramas. You can always start over with a different character , if you'd prefer to remain playing Vanilla. It's much more fun and rewarding.
Players who want to play max but don't have the funds to get there yet. They can either use changes to tbc or staying in the traditional. They can join new guilds, and begin to cheap WOW Classic TBC Gold raid nax entirely starting from scratch, with a brand new raid. They'll need to pay for a service to copy them to join with tbc. Since the original community of WoW has been dissolved this service must be free.