Although I concur with your observations; I know exercise, meditation, and supplements are only promote so much response. Of course they are effective, and tend to be more effective if you're already healthy, or have severe defect.
At the age of 17-19, I ran a lot, worked out in my room, reduced food consumption, meditation, and used dual-n-back. I would take 1 hour run on my sub-division towards the evening around 10PM. I was hallucinogenic, when complete I could feel my body rush with blood circulation, my brain felt good, and was more apt when home.
Pharmacology can elicit biological response not native, and many of the drugs I've used promote response I would not otherwise have. I've had very profound experience without them, but I understand I can provoke activation when wanted with drugs.
Dopamine agonism is the wrong way to go, unless you have parkinsons.
Go for the root cause.
Psychological problems causing it perhaps?
Exercise+Meditation, and supplements that induce potent neurogenesis will do far more long term than any drug that releases dopamine (agonists, amphetamines, reuptake inhibitors)