It's a downside on the "hybrid" that you can't get it. I think the tank on my RAM is the 32 which was the max at that time. Been really nice to have.
The hybrid gets better mileage, but I don't think it makes up for the smaller tank. I can't even remember what the "small" tank size is in the F150 to be able todo the ciphering. But I think the regular ecoboost is 20 mpg epa and the hybrid is 24...