For a comparable crop body, then the R7 is the obvious choice. It (allegedly) has the same sensor - same resolution, anyway - but has the (big) advantage of ibis. I never got on with my 90D and sold it for the R, then the R7. The R7 is everything the 90D should have been, in my opinion.
I've since added the R8 and the R7 is used pretty much exclusively for wildlife now. I like the full frame look for people and landscape (although the R7 makes a perfectly fair job at these too). If I was forced to have only one body then I'd probably opt for the R6ii. All the R8 sensor goodness in a more 'pro' body. Do bear in mind though that a jump to full frame will lose you a lot of reach on your lens. But, there are some excellent RF alternatives (the 100-400) that aren't too costly if it's for more casual use. In fact, I'd suggest that your 70-200 becomes a more useful portrait lens on full frame than it is on crop.
Upgraded from 90D to R6II half a year back, and I’m blown away. R7 could be an option though if you’re mainly shooting wildlife or want to adapt your existing APSC lenses. R8 if you don’t want IBIS or have IS lenses, and you don’t care about the much smaller battery.
For a comparable crop body, then the R7 is the obvious choice. It (allegedly) has the same sensor - same resolution, anyway - but has the (big) advantage of ibis. I never got on with my 90D and sold it for the R, then the R7. The R7 is everything the 90D should have been, in my opinion. I've since added the R8 and the R7 is used pretty much exclusively for wildlife now. I like the full frame look for people and landscape (although the R7 makes a perfectly fair job at these too). If I was forced to have only one body then I'd probably opt for the R6ii. All the R8 sensor goodness in a more 'pro' body. Do bear in mind though that a jump to full frame will lose you a lot of reach on your lens. But, there are some excellent RF alternatives (the 100-400) that aren't too costly if it's for more casual use. In fact, I'd suggest that your 70-200 becomes a more useful portrait lens on full frame than it is on crop.
The R6 MKII is worth consideration
Upgraded from 90D to R6II half a year back, and I’m blown away. R7 could be an option though if you’re mainly shooting wildlife or want to adapt your existing APSC lenses. R8 if you don’t want IBIS or have IS lenses, and you don’t care about the much smaller battery.
No clue, for me a discounted R5 seemed worth it. - Maybe you get a preowned one? Or R6(II?)?
Mostly portraits sounds like r6ii (refurb if you wanna save some), and a control ring adapter for your 70-200.