You could be on to something with the Fairlane / Falcon as a possible replacement for the Crown Vic. I think the size would work and with the 5.4L engine the power is definitely there, much better than the current Crown Vic and potent enough to be a contender to the DC Hemi.
I'd like to see Ford do something along these lines. If they'd throw-in a manual transmission, I'd finally part with my old Vic and if they brought over the Ute, it might be time to update the Ranchero!