They would have either increase the floors from 61+ or severely reduce the number of pomenders you acquire otherwise the challenge becomes piss easy. The whole point is how risky the higher floors are due to time constricts. That becomes nil and void if a wipe on floor 84 sets you back an hour and a half. It just makes easier, which defeats the entire purpose. Likewise, if you allow a second tier, people are going to ignore whichever offers less EXP. That's how 51-60 became the go to spam for PotD.