Cross-Faction PvE might even bring back ex-WoW-players. We know there's no "Enable Cross-Faction PvE" Button on your side and this might take some time to implement but this could change WoW forever.
Warlock PvE DPS Guide - WoW Classic: Season of Mastery - Warcraft Tavern
Returning WoW players' pre-Legion guide - Part 1: PVE
World of Warcraft Classic Best Class Tier List | PVP Best Class To Play
WoW Classic Best Class Tier List - Best Classes for PvE Dungeons and Raiding - Wowhead News
The Best Classes in WoW Dragonflight - Best Class in 10.0
Best Professions in Classic WoW (World of Warcraft) - Wowhead News
The Best PvE Hunter Build for WoW Classic - Odealo
The Best WoW Builds for all classes by Odealo [BFA 8.2]
Classic WoW - Class Picking Guide - Best class for PVP / PVE