You gave us the gross weight ratings for the trailer and the truck, but not what your trucks tow rating or payload nor any actual weights. Useless!!!
Get the trailer weighed, provide the truck specs, then ask for opinions.
As far as switching trucks...I don't see either of the options listed as a significant upgrade. You could gain towing capacity, but if your in specs today and your Yukon tows well, why change at all. In addition, you haven't given any price point for which you are shopping.
The lack of info will result in a lack of good responses.