Zardnaar
Legend
I think I have a solution.
@Zardnaar , would you agree that if bad saves were only "somewhat" bad and not the almost guaranteed failure leading to a shutdown (like say hold person) situation we have now, it would be a lot better?
The design goal here would be not "bounded accuracy" but, uh, "bounded suckitude". I thought about how to do this, and I was writing this post in a "this is a desirable goal, but how to make it simple" form, but I found a partial solution.
Saves should always succeed on a X on the dice, not just 20. Say 15 - so your chance of making a save (where "you" is both the PCs but also NPCs and monsters) would never be worse than 30%
Should it be 15? 18? 12? Should this number change with level? I don't know. But I think that I've demonstrated that it can be done in a simple, easy to use and remember manner.
Well saves could be a flat save (DC20 was essentially the old ones), could be 10, 15 or whatever.
Divorceing saves from ability scores is another option 3E and 5E both did this.
DCs in both 3E and 5E get double whammy from ability score modifier and spellcaster going up in level (Spell level or proficiency bonus) on top of more power spells.
Or massive rewrites of the spells or something like the 3.5 Warmage being the most powerful caster available.
If you skipped 4E its a 22 year old tradition now.
Spell DC could also be 10+ ability modifier.