I have the same truck.... 2016 ram 1500 4WD reg cab / short box.
My truck has the Uconnect 5.0 and 6 speaker base system.
Here's my advice:
Rear speakers - These speakers aren't really useful. If you do want to replace these speakers, I suggest a midbass speaker. Reason for this is that the seat belt covers 80% of the cone area. Any speaker with tweeters (2,3, or 4 way) are wasted here.
I personally ran Kenwood Excelon 6x9s.
Door speakers - Stock size is 6x9. Depth is your limiting factor here... consider 3" as an absolute maximum. Less if the speaker has a big magnet. Again I suggest a mid bass speaker as all treble will be lost blasting into the side of your calf.
Dash speakers - Stock size is 3.5". Considering that the rear speakers are compromised by the seat belt and the fronts are limited by blasting into your lower leg, a good 3.5 is an asset here.
I personally ran Kenwood KFC-XP184C which is a component set. 7" round mid-bass placed in the door and the 1" tweeter in the dash position. It fit perfectly.
In the end, my speaker selection sound very good with the uConnect 5.0 powering everything.
I plan on eventually replacing the uConnect 5.0 with a DDX-793, using a iDataLink Maestro to keep my factory menus.