Good luck, Len, but, while obviously Pooroldmackley could win today, on a general point of principle going forwards I think your system is going to come unstuck over Jumps if it's rating a rider like Eleanor Williams ahead of a rider like Gina Andrews based on this notion of "recent form."
There's no reason why Andrews should have any recent form - she's just not had a lot of rides lately - but that doesn't diminish her ability in the saddle.
And pretty soon, you're also going to have situations where your system can't have a jockey in a rules race based on recent rules form when they've ridden a treble in a Point the previous weekend.