As a next experiment, give Atomoxetine a shot. Works nicely for me and is not a stim. I feel it makes me more emotionally involved/interested in whatever I'm focusing on, so very easy to get into flow states, provided there are no distractions around. It doesn't warp time or change your mood/personality like the typical stim based meds. It does affect appetite, so if you are trying to lose weight, it becomes very easy.