91 and 93 is not bad for a 30 handicap. If you really hit a 240 yard drive with a slice or hook "often", I would think it would be a lot more than 3-4 strokes savings. Each time you do it, you could lose 2 strokes or if playable 1 stroke?
We all have many facets to fix. I am currently only working on one specific aspect of the full swing.
That is the distance I hit if it's well hit or a bit of push. For big slice or hook I find it varies a lot but ~210 to even below 200 which is even shorter than my 4 fairway metal. Often distance is not a killer but hazards and trees eat up many strokes. For the handicap I don't play enough to keep my official handicap
For "full" swing, one thing that really helped me was not swinging full. Making 75-80% of swing and grab one club longer than my range distance made rounds a lot more enjoyable and lower scores.