I am thinking that the CX-70 will be around the size of a Ford Edge at maybe 189-191 The CX-50 is 6 inches longer than the CX-5 and the CX-90 will be growing a bit so there will be about 15 inches of length between the -50 and the -90.
BTW, the CX-70 will not have a V-6, it will be an inline 6.