Welcome to the forums and congrats on saving several steps (not like me) and going with a tag DP right out of the box. The ONLY con of a tag is two more tires, $1200... in my case every 10 years. For $120/year I get great handling, 9,000 lbs of CCC, plenty of room... 40+feet.
Bill S is correct that the longer the coach the more it's going to drag the hitch and the tag will only help some... it will only support the amount of weight that it's in it's air bags. This is usually around 40 psi or 6000+/- lbs when traveling. With air leveling I'm able to raise the coach up about 4" which I have to do to get it into my MH bay. This increase the psi in the all the airbags increasing their load carrying... for the tag, probably above 10,000 lbs. Having gotten hung up trying to get to a friends house with the coach already raised up there is one more trick. I manually raised the back of the coach and lowered the front... giving the drive tires enough traction to move ahead.
While I'm partial to the Monaco/Beaver RR10S suspension (do a search RR10S) your other two brands have a good rep but they do not use the outboard air bag suspension. I think you will find the wood work is superior in Beaver's and a close second in Monaco's.
I doubt you will find much difference in floor plans unless you think you need two baths or a front kitchen. About the only other difference (major for some) is the TV location. Some do not like the TV above the front seats (sorry, they are not Pilot and Copilot seats found only in airplanes, but I digress). I like laying on the J couch to watch and DW likes the Euro chair and rarely are there more than two of us watching the TV inside. I'm sorry, but the DW is along for the ride... I do 99 percent of the driving, all of the repairs, all of the blue jobs, and most of the planning of what, where, and when. Man up, the handling and reliability is more important than the floor plan.
Good luck in your search, take your time, this site is a good place to get educated... lots of info in that search box at the top, especially if you will search in the archives... more than a year ago.