Goat's milk is more acidic, pH targets are different. You're fine so long as you drain completely before you hit about 6.2. If you overacidify before starting to wash, what you can do is use a higher volume of water, which you did.
MM100 will just give you a more flavorful cheese. MA11 is somewhat bland in gouda.
There's nothing really wrong with your process, seems fine. Not sure what other help to give you because I don't know the full details of your process or amounts.