I am in the same boat, I don't have anymore car seats to put in the back just a booster now so I don't need as much space as I did with the Silverado. the slightly bigger Colorado ZR2 would be a great alternative. I am only 6ft so I don't think I will have the driver seat space issue.
I don't know if its any different from what I have in my Tahoe, but I don't have any data packages on it and it still shows me the speed limits. The only place it goes blank is on private roads.