I was wondering if using various multipliers is better than a stagnant 3x IP and 4x oop.

Against a 2.5 rfi \ 3bb rfi
IP
Vs utg 4.0x ~  10 \ 12
Vs MP 3.5x ~ 9 \ 10.5
Vs CO 3.0x ~ 7.5 \ 9.0

Oop
Vs utg 5.0x ~ 12.5 \ 15
Vs MP 4.5x ~ 11 \ 13.5
Vs CO 4.0x ~ 10 \ 12
Vs BTN 3.5x - 9 \ 10.5

Using bigger multiplier vs utg because UTG has tighter RFI range and thus should want to fold less often. Using 4x IP and 5x oop to charge this range. We do cut back on pot odds, but a lot of players can't resist folding AQo or KJs vs larger sizing. As ranges get weaker, such as btn vs co, there is a lot of dominated hands and air that have to fold, so I think just going 3x is fine.

Thoughts?