I'd recommend getting 2 or 3 fronts and 2 or 3 rears and change them for each different track as needed.
At present I have 11 and 12 fronts and 49, 51 and 52 rears. 2 or 3 of them are pretty worn, but not so much so that I can't use them if needed.
I'm currently on 12/51, but will experiment as needed.
I'd try going with a 14 front at first - it's cheap and will provide a BIG difference.
You could also look for a 46 for the rear.
Right now you're at a 3.69:1 ratio. If you switch to 14/50, you'll be at 3.57:1 - not that big a big difference. 13/46 would be 3.54:1. 14/48 would be 3.43:1.
Then again, going the other way might solve the problem as well - it just depends on which gear you want to be in at a particular time - 2nd or 3rd . . .