Assuming that Classic WoW will be server VS server again with the same way of doing Battlegrounds
Little doubt Bnet integration will happen, we will be able to talk to friends on the other faction.
While also having third party voice chat being very popular these days like Discord.
You could potentially strike a deal with friends, Queue up at the same time with 10 people on a countdown for WSG.
If I remember it correctly. Battlegrounds had numbers, so you could check if both teams get the same one.
(A bit like we used to make 40man AV premades with "Preform AV Enabler Mod")
One team stays passive and gets farmed on the graveyard while the other team runs the flag.
The round will be over very fast (6 min) and during the next round the other team returns the favor.
While this may be very boring, it will be very efficient to rack up those HK for ranking and reputation for gear.
Possible also avoiding Queue times.
Not sure what a possible fix could be for this without breaking the "Classic Feel" other than making it a ban able offense.
Ofcourse we don't know what Classic WoW will be like, was just a random thought that i had.