The CR-V is considerably roomier than a vibe, IMO. We have the vibe's twin, the Matrix. We have borrowed MIL's CRV for a road trip- it is definitely roomier. The mileage also sucks compared to our Matrix.
I would look into a Mazda 3 hatchback, or maybe a Honda HRV. IDK how tall your kids are or might end up being, but if they aren't going to be real big, the Prius might also work. It has a curve to it so the back seat seems kind of not tall. But my girls are both petite, and I am only 4'11", so I don't suspect it would be a problem for them in 10 years. (Our 2005 matrix will probably be replaced in a couple of years, kids are now 5 & 7 and the little one is still rearfacing.)
But I have a thing against SUVs, even smallish ones like the CRV and RAV4.