A lot of the '68-'70 B structure was from the '66-'67 Bs - I'd bet Chrysler just saved the money on wagon roofs, not prioritizing that element of styling.
I had a '70 B wagon, and I can understand the point made on the roof styling, but it didn't bug me.
To my eye, the early B and the 71-up B had the nicest wagon roof styling.
Also fond of the Forward Look stuff, come to think of it.
FWIW, ain't nothin' you can do to make a '70 Coronet appealing to me, but it's OK that we don't all like the same things.