Yeah I think that if you got a tuner with a nicely programmed "daily driver tune" you'll see some benefit.
Mike @ 5Star does a nice job with the 5.4L with the SCT products.
The guys at PHP do really well with the Edge converted to Gryphon. This is the heads up dash mounted display showing gauges, etc. whereas the SCT is just a plug in, program, and remove, unless you get the Livewire model.
The tuner will give you slight HP increases (maybe 10) and much more useable torque at a much lower RPM which really aides your daily driving. That combined with firmer shifts, a better torque converter lockup strategy, and slightly better driving habits should yeild the MPG increases you're after.