The "acquire all life-cost items on floor" challenge item should be moved deeper. I've seen it spawn on floor 2 and 3 where I have had, at most, 16 hp.
A mere three 3-cost items will cost, in total, after the increasing costs:
3, 3, 3
2, 4, 6
=====
5+7+9
21 HP.
Except I have never seen a shop spawn with three 3-cost items, usually there's only one (and yes, I'm looking at prices before buying something!) and the other two are 5-cost. That puts my minimum viable HP at 26.
Actually, better idea, don't spawn it unless it would be possible to have enough HP. If there's two life-shops (which I've seen) the costs just get crazy (60 hp for all six 3-cost items). I'm fine if it makes an optimistic guess, assuming I can find shards and a couple of hp from leveling up, but walking into a level with 9 hp and seeing that challenge...I don't even spend the time picking it up.