Truck or SUV, full size or compact

[Onestep]

Ok peeps, need some input.
We are going to have to replace the car (Malibu Maxx) in the near future. We have a full size Tahoe (2WD) as our other vehicle.
The Maxx averaged 26-27 mpg, while the Tahoe gets about 17. The wife typically drives the Tahoe due to her work being much closer to home. I drive the other due to a 76 mile round trip every day.
We want at least one vehicle with 4WD so the new one would need to have that. Plus it would be nice to have a towing capacity of about 3500#, but the Tahoe can handle that.
I like the idea of this one being a truck as we have the suv covered.
The advantage of the suv is that all the cargo can be safefully stored within the vehicle and the seating is better.
The advantage to the truck is you can just pile the crap in the back but seating is limited unless you get a crew cab but that reduces the bed area. There will typically only be us two so seating is not a huge priority.

We cannot afford new so we have looked at Jeep Cherokees (not the the Grand Cherokees) even though they are typically older but there have been some nice ones around and they can be substantially modified.
For smaller trucks we've looked at the Ford Ranger models and Tacoma, mainly extended cabs. But the price of the Tacomas may be out of our range.
The tough part is most everything averages less than 20mpg (and closer to 17) unless you can find a 4 cyl. but they typically don't have 4WD (not that I have been able to find).

Any suggestions on higher mileage vehicles I may be missing or should I be leaning towards a full size as the mileage isn't that much less?