When I was a working sports photographer many years ago -- before soem of your people were born even (LOL), my "motor drive" was my thumb. Then I was able to buy an F-3 wih a cheap 300mm f/4-ish lens for all my sports. At the professional sports games, I was he only one without a REAL or PROFESSIONAL 400mm lens. I was looked down on in a friendly way, the REAL sports photogs not accepting me a SERIOUS. LOL. Well, I bought a house , then another, then another. THAT was where my money went. And I was very often able to outshoot the "REAL" sports photogs most all the time. I worked with what I HAD. I adapted and overcame. I actually hate sports and the jocks that participate, but I learned the sports never the less and KNEW WHEN to shoot. My best shots were usually the first one or two. I did not NEED 10 FPS!!! Our predecessors used 4 X 5's and had only ONE shot. They had to make it count! As a U.S. Navy Photojournalist I was admonished to remember that "The camera does not matter. It is what's six inches BEHIND the camera that matters.
I get 16 X 20 prints that are SUPERB from my D-200, My D-300 is even better. I like my prints contrasty and saturated so why would I need a full frame sensor if I eliminate much of the subtle tones it can capture?