Aside from the fact that you were never the target market for this camera: would the R3 have radically changed your birding photography with 45mp at 30 fps instead of 45mp at 20 fps?
It'll have the ability to grab more of opportune moments at useable resolutions, so yes. It would definitely improve it. Dramatically so? Most of the time, maybe not, but during special circumstances/opprotunities? Hell yeah. As the R3 stands, it's a down grade in almost every circumstance