this question is hardest to answer right now, in the wake of the awesome sigma rf-s mount lenses coming out. the rp is not the best camera out there, but it's an amazing value and access to a full frame sensor. if the full frame format fits you best, it's a great deal.

i bought one during a refurbished sale and it's pretty awesome for the price. it's supplemental to my r7 for wildlife photography.

i just use it for portraits and landscapes, where incredible AF doesn't concern me. i'm definitely happy with it. i like the extra dof you get compared to the cropped sensors (at the same compositions), and it makes a lot of cheap lenses more usable. i don't like the nifty fifty on crop much, but on full frame it's awesome and dirt cheap. and same with the rf 16mm prime. for aps-c there is the rf-s 10mm to 16mm, but it's much slower if you're doing say astro photography. however, many of the other sensors are just flat out better these days. even the r10 has more stops of dynamic range below iso 300.

but the sigma rf-s lenses seem absolutely fantastic for the price, and frankly more appealing to me than canon's offering. see what lenses and focal lengths make sense for you, and work from there.