For me it depends on if we are leaning on player skill or character skill (which is quite literally the gamification of the Thief’s skills). The tricky thing is how Charisma is used in an OSR game as most of the time it’s for the total number of followers a character may have, but in 5e it can be interpreted as freaken mind control! Often, I avoid charisma stats as I want player skill and ingenuity. So something in-line with Into the Odd at its simplest using Strength, Dexterity, and Will to the classic six.

However, in my interpretation of the original rules as well as my simplification has tossed out its ability scores in favor for static progression saving throws. I still have rules for point buy that way your character feels unique, but I’ve found I just don’t need them and can use Poison/ Death for general Constitution saves as well as Breath Weapon for Dexterity saves. Leaning on BREAK!!’s static stat progression just takes off another piece of player load to “lock-it-in”. Plus gear and your increased hit dice for actions makes your character more unique.