Taz, I've got a similar situation: 2006 Dodge Ram 2500 MEGA CAB, 2WD, Cummins Engine + Me, 1 Wife, 3 Large Dogs
Because of payload issues, I've been eyeing the "light" fifth wheels on the market. Not a ton (pun intended) to choose from which also limits the number of floor plans options.
However, I came across this one which puts all 3 dogs in the front bunkhouse and the master bedroom in the back. This gives the boys their own room which I can even close off if I choose and it gives us a bigger master bedroom with more headroom.
Check out the: Jayco Eagle Super Lite 31.5FBHS

There's a couple of other light fifths on the market that you might be able to get by with.