People need to wrap their heads around the idea that Canon's mirrorless system does not have to follow the DSLR market segmentation. In fact they haven't so far, so why would future releases?
Canon currently has seven full frame cameras introduced at seven different price points and with seven different feature sets. (1D, 5D, 5Dr, Ra, R, 6D and RP). There are two additional mirrorless models rumored: A high resolution model and an action-oriented model. I don't expect that either of these two will exactly mirror the available DSLRs, although the high resolution model may be the only true "replacement" for a DSLR on the list.
Canon has said they intend to offer models both above and below the current mirrorless offerings, although it is hard to imagine a mirrorless model below the RP, but who knows?
It is possible that a second generation R may arrive sooner than the usual refresh rate, in part because the line is new so it would't be surprising to see Canon update models more quickly for the first generation or two. It's also possible that Canon leaves the R in the lineup and offers an upgraded version with two card slots and some other improvements. A big unknown is whether or not Canon views the single card slot as a hindrance to sales. Just because people on the internet endlessly obsess over single card slots doesn't mean buyers care that much.
In short, people need to quit worrying about 5D and 1D equivalency when they discuss the R series, as I doubt Canon will ever make mirrorless bodies that are true equivalents to their DSLRs.