Talking 20 mpg for a 4x4 full-size truck is unheard of!
You can get the front center console in two configurations, either the center console like yours or a folding center seat with cup holders and a tray on the back of the seat. So, I'd get the folding version. I've ridden in this seat before, and it's surprisingly not bad because the truck is so wide. At the very least, it should be useful for the dog when driving 5 people. I'm not a fan of the dog riding in the bed. Just too dangerous for a pet I love.
I've never liked the OEM GPS's because the ones I've used don't do well with forecasting and routing around traffic. But I realize that's really only a big problem in gridlocked metros, like the SF Bay Area where I live. That's why I like CarPlay so much. I can use the traffic apps I love, Google Maps and Waze, on the fixed screen.
Now that I think about it, I've used the OEM GPS in the Superduty in Utah because Google Maps and Waze were getting me lost. Ford's mapping worked quite well on the backroads of Moab and Indian Creek country. Google, Apple Maps and Waze work so well near me, but they fail me when I get to other areas of the country. It's probably because I'm so close to their HQ's.
You can get Sync 3 in the XL and XLT, either through an equipment package or the STX package. I love car play so much in my friends' cars, but I've been living all my life without it. So do I really need it? I don't know.