I agree with Asari, try VPR. Yes, it's fast, but its control scheme is very simple, and what it asks of you is very straight forward. It also has some strong ranged attacks which will help with learning fights as a melee.

As someone who is on the ADHD spectrum, my favorite melee DPS is MNK. I find that my mind wanders playing the simpler/slower/more static jobs, and leads me to make more mistakes. MNK has enough going on that my brain can stay preset. You can also try MNK if you are feeling adventurous.