Funny you posting this now as tonight / this morning I’m building a single player throw barbarian. I’m farming Countess for runes and experience. I’m level 19 right now and have never crossed into the Tamoe Highlands. On /p8 it didn’t take long at all and I likely could farm the tower until clvl 25 without much stress of not seeing experience gain.
I’d suggest if you do this again with another character that you at least bug Andy by going out her portal and straight to Warriv and to act 2 without going anywhere else in between. This way when you do kill her from then on you are getting quest drops every time, but never have to go to act 2 again.
At clvl 19 he has a Stealth armour and a Nadir barb helm with +2 throw mastery.
Though I had no idea we could get our characters to clvl 40 in act one, I do know we can grind to clvl 80 in act 5 nightmare and clvl 90 in act 1 hell, we can also 99 just farming Chaos, or just Nilh, or just Throne/Baal. I hope that wasn’t a spoiler for you.
Very cool the grind you’re doing, I have huge respect for those who actually play the game.