Reviews of various Canon RF cameras:
So what would Thom get? The RP was a bare bones, entry camera. You bought it because of price. The R8 is the new entry level RF camera, and it's quite good for the price.
The R3 is certainly an excellent choice for those looking for a fast frame rate flagship mirrorless camera akin to the 1DX, but I don't regard the R3 as a more general camera due to the low pixel count, among other things.
The most well-rounded of the full frame cameras is probably the R6 Mark II, which brings the best of Canon's DSLR world into the mirrorless realm pretty much intact, while adding some mirrorless-only aspects. The R5 is the top end if you need the pixels, but the R6 Mark II is the camera most should be looking at.
Finally, with RF-S now a thing, the R10 (basically a mirrorless Kiss/Rebel) and R7 (somewhere between the 90D and 7D II DSLRs) are well worth looking at. The R7, in particular, is a solid camera capable of most everything most people would need. I'd tend to avoid the R50 and R100, as they are stripped of features.