i'm getting 21 on the highway. but i run a little heavy because i have a 27 gallon aux gas tank mounted in the bed. not bad for a 27 year old v6, imho.
don't know of any radio like you're wanting really. i have an older panasonic that just has the typical green display so i don't get distracted by all the bright colors of the new ones. it also has weather with SAME reporting that i need. i'm using Sansui 4 inch speakers, again older and not being made anymore. they have a little deeper bass than the other pioneer's, dual, etc. speakers i tried.
good luck with your truck, and have a Happy Holiday!