Hmm. Lack of any missile troops at all is going to give you a problem if they stand off and shoot you up, fair enough. Though if they have vanilla archers and they are firing on FS its worth seeing how many causalties you are actually taking before moving out of a good position. Often its best just to take the fire.

I'm not too sure about the position either, height offers a big advantage in defence. I can see why a valley might look good in terms of flank protection but if you don't hold the hills at either end the protection turns into a launchpad for enemy units. might you have been better set up on the hill?

I second the advice about not looking for trouble (and not matching cav with cav if you don't have to). you could try a shorter line, maybe three FS and 2 FMMA, and stack up the remaining 2 FS and 3 FMMA in two columns behind the two units on either flank. Put the cav in the middle. This way you have a reserve force on each flank to either turn 90 degrees to meet a flank attack, to pop out and extend your line if need be, or to come round and flank as the chance presents itself. Ignore the enemy cav poncing around unless and until it actually commits itself to an attack.

You are quite cavalry heavy too. You might consider taking all the cav out of the Inf formation (but not putting it so far away you can be taken out in detail) and having it some way out to pile round en masse once the enemy is committed to your infantry. 4 MS would have a fair impact, I'd leave the hobilars maybe. You might have to move your inf forward to make him attack, if he shows signs of wanting to chase your cavalry instead.