I remember the struggle leveling my shadow priest back in the day and always dealing with higher level alliance(beating most). I'm playing a mage and It seems like it's impossible on this server because if someone is just 2 or 3 levels higher I get resisted so much that the vanilla mana pool just can't handle that. If someone 5+ levels attacks me I basically just accept my fate because I can't land a spell for my life. I played retail vanilla all the way through BC and it was never this bad, sure you'd get a resist here or there, but I get resisted like 5 times in a row or more.
I tried sheeping a Skull(seemed to be 60) rogue and could not after a full mana bar. This is clearly not working as intended because higher level's already have a gear and stat bonus vs lower levels. Now we must also deal with ridiculous resist rates that just didn't exist on classic. A player just 5 levels higher is godly and impossible to kill, while I remember killing skulls on many occasions (with help) back then. My shaman friend and I could not kill a player just 10 levels higher because of insane resists.
I also have the talents for lowering all enemy resistance by 10 and the 6% chance to hit with frost/fire spells. I doubt anyone is running around with anything past their race resistance which are normally just 10. So I am hitting most targets at -10 resistance and a bonus 6% should not mean a 75% resist rate on someone 5-10 levels higher.... This is not PVE but it feels like it.
Don't say it's classic because I played classic and yes it was hard but I could kill higher levels if I was more skilled, While on this server you cannot.