I don't think you should compare road sprinting to track sprinting. Yes, they use the same word, but they are very different. A sprint after a 45 minute crit is MUCH different than a match sprint over 750-1000M from a slow-ish first 400M.

Look at road sprinters of any level. When they race track sprinters of their same level (local, regional, national, international) it's the same story. They get dusted. Same would happen if a track sprinter jumped into a road crit of his/her same level. He'd be dropped long before the final sprint.

Road gearing is different than track gearing. It's not comparing apples to oranges but more like comparing apples to pears.

Generally speaking, Leg speed is a function of muscle fiber type. Basically, how fast can your body make them contract with sizable amount of force and recover and do it again...measured in milliseconds. If you got it, you got it. If you don't, well... that's like me asking for fatigue resistant muscles. Anecdotally, when I first started racing...like my first month I had 130-140rpm legspeed on the track using beginner gears. I was very fat and very untrained...but I had natural leg speed. But, try as I might, I still get dropped in long track races. I remember the first time I finished a 20 lap points race on the lead lap. I shed a tear...

I've always leg speed, ever since I was a kid. I could always beat my track-star cousin racing down the street...but he'd leave me puking on long runs. He was a middle-distance specialist that medaled at the HS state level.

I think you can fine-tune what you have. If you have a big engine (lungs), big legs (strength), and a small frame, then maybe look to using bigger gears.