Regardless of whatever specialty you are in, always remember that medicine is a business, and how much you make in any field will highly depend on your business practices. In other words, the local demand for your services, what you will be able to bill for, how readily primary care providers will want to refer patients for your services. Of course there is always the option to go on salary for a hospital or a university (academics blech), in which you do make more in a procedure rich specialty, but it will almost always be less than your private practice counterparts. I like the idea of teaching residents and medstudents as the next guy, but I'm not taking a potential 50-100K paycut just so I can feel like the dude in "Stand and Deliver".
Neurosurgeon who works in the town an hour and a half south of here makes well over 7 figures, and it has less to do with how good a surgeon he is than you think (although I hear he is excellent). He amassed enough capital to purchase the only PET scanners in addition to several MRI machines in the area. Radiologists work for him, and he gets a cut of every scan he and his partners send for. He basically gets a piece of every work-up test ordered along the way of Dxing the spine and brain pathologies that run through his office, from the initial consultation visit to the pathology slide thats read intraoperatively. Just like Tony Soprano, he gets a taste of everything that goes down, and it has made him a very rich man.
Obviously, this is easier to do in a procedural subspecialty than in a non-procedural field. It is also easier to do in a relatively underserved rural community with lots of insured middle class professionals (big university is located there). However, I could imagine that even as an FP or Pediatrician, clever business practices can still make you a very wealthy physician. You just need to be able to provide a service that will make ALOT of people want to see you and your partners, and if you find yourself at the head of the pack all I can say is BUY BUY BUY. Purchasing medical equipment, office space, PA's, NP's, and young physician attendings is not all that different from the industrialist who buy factories and machines to manufacture. If you wanna be a rich doctor, then you gotta get excited about capital investments and growth. Know your community, know what it can provide to its patients and what it can't. Fill in the gaps and you'll be rich.
This is much more difficult to do in oversaturated places like NYC, LA, Chicago, DC, or Miami. You gotta go to where there's a demand, and where people are tired of driving 50 to 100 miles to see a doctor much less a specialist.
You wanna be a rich man, think less like Ben Carson, more like Jack Welch.