While I am definitely a fan of some spells using attack rolls, I defintely do not want to see a return of NADs, or even Fort-Ref-Will saves. I still really like the idea of a save for each stat:
STR save - resists - monster grapple attacks, hazards like falling boulders
DEX save - resists - any spell or hazard where you dodge out of the way
CON save - resists - any spell or hazard that attacks the body or life force
INT save - resists - illusions and any hazard where a keen intellect would help you
WIS save - resists - mental attacks, fear, or any other effect that does not clearly fit into any other save
CHA save - resists - charm effects, any effect that overcomes your personality
STR also deals with web spell, and other such movement reducing effects.
DEX deals with two types of effects, those that you get hit by and then you try and reduce the damage "by some means" to half damage. It also represents effects where you either fall in or you do not. This has always been tricky on in my book because you also often have skills that overlap in the same area (tumble, athletics, acrobatics or whatever). You also have an AC which also works in this areas too. Reduce damage from attacks by making it harder to penetrate your armor. So a lot of disparate elements that are in the same area mechanically or conceptually.
CON saves are easily separated out. Basically fortitude or PPDM save from days yonder.
INT there are currently no spells that target INT, Mind flayers mind blast goes against INT and that is it.
WIS is what you say, a catchall for anything that does not fit into CHA, and since there is only one effect that targets INT, in the current game, it is basically not a save.
CHA it peeled off some compulsion effects (not all though) from WIS.
Ok so how do I think it should be rectified?
STR seems fine, they could remove the contested roll and institute a STR save instead for grapple and various maneuvers. This would make it very important.
DEX AC should work to reduce damage from fireball and other damage effects. Gorgoroth called this one out in the other thread and it really made sense to me. Fighters should be able to defend themselves against damage with their armor. Then there is the dodge aspect and if skills that thematically should help you dodge should be there to help. Well it depends on the skill system. Lets assume that the DM chooses not use a skill system for the moment (to make it easy). Yes, this is where DEX should be to dodge or not fall in, where not dodging would cause the effect as opposed to not saving means you take a little more damage.
INT They have made a non-save, a dump stat when considering saves. I dont like that personally. For perception they have made it INT or WIS check to notice something in the bestiary, that has not been trickled into the spell section yet. I also like the old disbelieve to be INT based and not WIS based.
WIS ok so here is where I would like to see some DEX peeled off and placed here, make it perception and awareness. Surprise can be a WIS save, heck initiative could be a WIS check, orient yourself to the battle faster.
CHA Here is where you resist the brunt of mental attacks. Compulsions, fear, phantasms, mind blast, mid control and all the host of other attacks on the mind.
One other point about magic items. Since saves are more expansive. I am not sure that the protection and resistance magic item qualities should remain the same. I can see protection for physical saves, and resistance for mental saves. Physical could also include AC. So, Protection would give you +X to STR, DEX, and CON saves and AC, while Resistance would give you +X to INT, WIS, and CHA saves.