I re-rolled from Horde to Alliance to be with my current guild, who has several raid teams of different difficulties, and is incredibly friendly. I suggest being open to both Alliance and Horde, and being open to going to different servers. I don’t know how populous your realm is, but starting a new char or server/faction transferring might be worth for the fun guilds provide. You can try hopping on different realms and just chat around. When shopping for guilds look for guilds that advertise as social but like to do end game content too. Ask how many members they have, how active it is etc.
There was a recruitment ad for a guild posted on the new/returning player forums that does raids in the weekend evenings and caters to people starting content.
Message the person here and see if you can get some info, sounds like it’ll be right up your alley.