I'm honestly going to have to go with a -1 on this one. Although the concept in itself is neat to think about, the fact that rolling is almost purely based off of luck is a hard contributing factor to why I think that this suggestion wouldn't get accepted.
I like Yonio's idea. Giving attributes to players to effect their combat experience. Perhaps something attribute related could be added to allow players to go outside the normal "SRP human" boundaries, rather than allowing them to have higher rolls (For example, if you grind push-ups, you'd be allowed to grab someone and spin them around simultaneously, not necessarily allowing them higher actions for every roll). Not to mention it would cause a lot of distress mid scenario when people are now arguing attributes on top of permissions.
Lastly, players should be roleplaying realistically anyways, and P2L is in place as the preferred combat style of SRP (which is the act of applying realism to your combat scenarios).