>>536202813
You don't really go by amount. Generally you want to end up around level 8~12, most likely 9ish, by the end of day 1 (including the night boss). After level 4 don't bother killing the bosses of stone forts or cathedrals as they don't give passives or purple weapons. Clear gaols, ruins, wooden encampments (the ones with all the wooden fencing around them), the castle if it's in the circle day 1 (skip basement if it's BBH). You pingpong between those. Day 2 you usually bee-line it to the shifting earth while sometimes killing the red bosses along the way.
As this anon pointed out: >>536203004
if you end the run at level 7 or below your routing was quite bad. 8+ is perfectly fine with good teams ending after day 1 boss at 10~12.