While it is really fun and exciting to have the cutting edge technology its not necessary to make fine images. I myself went for R5 and have enjoyed it immensely but my son is making extraordinary images with my old 1DMKIV and a version I 500mm f/4L lens. I kinda miss the 1.3 crop sensor .... made a lot of sense for birders.

I am most likely going to skip the R3 but I don't know about the R1