Do I need more t-shaped??

[KnottedYet]

I experience chaffing on the inner thigh at the bikini line towards the back.

Pretty much the classic sign of a saddle with too gradual a transition zone from nose to sits for the particular angle of your hip joints.

A more T-shaped saddle would probably help. Look for a narrower nose, that might help.

Width at the sit-bones doesn't cause chafing (since nothing is moving there) but wider saddles sometimes have correspondingly wider noses and so more gradual transitions.

Transitions are where things move.

Transitions chafe.