I would think a majority of critical hits or crit-range would come from you ability to pick a weak spot on your target which would require dexterity. Where as "Strength" and "Weapon Quality" would effect how much damage per hit. Then why not have the crit multiplier be a sort of die like 1d4 but where certain prestige classes or enhancements might increase that die up to 1d10 ect.
CritDie: 1d4-1d10
DexCrit%: 5% at 20/20 +1 to Dex = 10% or (19-20)/20 ect.
StrDie: 0 and lower 1d2 (1.5) -> str+1 = 1d4 (2.5) -> str+2 = 1d6 (3.5) -> ect where die = 2*(StrBns)+2.
damage at str+10 would be 1d20+2=1d22 = 11.5 damage per hit average. If not enough damage at start you could just start at a higher die and still scale up an extra 2 sides of die/str.
so then average damage might look like
(Seeker+WeaponMod+StrDie)*(DexCrit%)*(CritDieAve)+ (1-Dexcrit%)*(WeaponMod+StrDie)+(AveMagicEffects)
We could then possibly have certain feats that would allow you to use other attributes in place if needed for different classes. For instance intelligence ect.
Haha a big change it would be but I think it would put most weapons on about an even platform.
Then take away weapon feat requirements so people just use more weapons they like rather than which weapon has certain crit features ect.
Then to make weapons unique we could instead give certain beneficial effects that kind of go with that type weapon.
I doubt they would make this big of a change but I thought it was a good idea actually.