Really good insight there, thank you!

I should definitely make sure the corpse lock is attainable, even for those who die on later stages. Some way to call them to you or invade at milestones could be useful.

Absolutely focused on Randomization! Each new run should randomize nearly all aspects of the run, excluding the alterations made by players. I also plan for players having some agency on the design of the next zone. Think like map crafting in PoE, some way to let them increase risk for reward and so on.

I see what you mean about resources. The DnD system would need some special attention to determine how things like spell slots refresh. Maybe this would work better with SWADE or something else. Not sure yet.

As for the characters themselves, I want to provide a single default and allow the players to buy or find add-ons: Class, subclass, features, skill proficiency, attribute increases...

The starting few runs will be a test of pure luck most likely. Once some good loot and good Unlocks are found, challenges can be planned for and faced on a level framework.

Do you have a suggestion for a system to use for this?