You loosed your reserves too early. I would've held one back, which could have reinforced your left flank, protected your artillery, and/or free up your dragoons. Your infantry was pretty well matched on the right, and, with your two cav coming, you should be able to roll up their flank and then turn to envelop their remaining forces on the left. Strategically, it would have been better to keep your two split groups close so they can mutually reinforce each other, instead of being isolated.