I was able to beat GR70 with 1.3M dps and 25M surv, when I tried to go GR75 with that stats I figured out that I can't kill mobs with enough speed sp the timer is running out faster that mobs counter. I spent ~70 runs on leveling gems and finding ancients items, so now I have ~1.9M dps and 40-120M surv and... I still can't beat GR75! Looks like mobs are scaling on my gear: more dps I have - more armor they have. What speed I had with 1.3M - the same speed I have with 1.8M!