Said in another thread and just thought to share here, I know it'll make it easier but I think it's fair. Every 50 levels you checkpoint, if you fail you can start there. At level 199 and hate your RNG (as an example someone made here) ... sure you could reset, but you'll have 50 levels to go through with potentially just as bad RNG. Easy to represent too, just star (UI mark) the 50 level options once you reach them consecutively without dying (then you can start from them and still count for achievement).