From what I've seen, you coulden't really go wrong with any of them. I personaly prefer the looks of the 12 inch head models vs. the classic series (classic, classic omega, classic III), but thats just me. I've always found the 15 inch heads to be too large but if you have a larger home then you would be just fine.
Those Lincolns sound nice, but I prefer the Mark IV and V myself. 95% of the time I'm a GM guy (Buick and Pontiac especialy) but if I had to choose a Ford it would be a Lincoln from that time period. Regarding gas mileage, have you ever considered swapping in a small block engine with a overdrive trans? I don't know how much work it would be but I'd look into it before I gave up on big cars entirely.
