Highest character level without mapping

I feel that running piety runs give for me more exp then level 66 maps at around 70~77. At level 76~77 is where I usually stop doing those runs for exp.

Although, on invasion on my elemental wander, I went to 80 there, felt more safe doing those runs then doing maps.

I think it's reasonable to go up to 81~, but after that, you'll be only gaining about <1% per run.