I'm not a long-timer, nor am I an expert. But I'll share my thoughts as I made the same choice you are working on.
First, I have a lot of experience pulling bumper-pull trailers, so a TT is not an issue for me because of towability. Fifth wheels can be quite a bit easier to tow and maneuver because the pivot point is right over your truck's rear axle. And they usually offer an interior space bonus because of the front overhang, and with more interior space comes more storage! There is also less of an issue with the distribution of the weight in a 5th wheel since the weight is centered between two support points (truck axle and trailer axle(s)) where as the center of gravity on a TT is back nearer the trailer axles.
Because of the need for headroom in a 5er, the front can get pretty tall which could lead to clearance problems with low-hanging tree branches, old bridges, carports, etc. And the 5er will have steps inside which can be a little problematic for old knees (like mine) or on party nights. As mentioned in another post, you would also lose the storage in the truck bed. And 5th wheel trailers are heavier.
With a weight distribution hitch and a little bit of intelligence loading the trailer, the TT should also tow just fine. An anti-sway device on the hitch will help a lot. There are weight distribution hitches out there that don't require an engineer to hook up and unhook, so they're not a problem to use.
I'm going fulltime solo, so my trailer needs are modest. I wanted a "smaller" trailer to allow boondocking while having enough room inside to live. The way I see it, i use about 9 square feet to live in (unless I'm laying down, at which time it jumps to about 20 sq ft) so the overall size of the trailer is for me based more upon the features and rooms than the absolute size of those rooms.
I wanted as large a bathroom as is feasible. Queen size bed is sufficient. I wanted a kitchen with real counter space, since I like to cook and need to spread out. I wanted a dining table and chairs that were moveable, rather than a built-in bench and table since I don't need that space to convert to sleeping space. I wanted a comfortable couch for lounging and watching tv. I wanted storage room in the truck, since I plan to install a gasoline transfer tank for the generator and an extra water tank. And I wanted as much space in the living area as I could get.
Armed with my wish list, I started looking at floorplans on the internet. I looked at new and used, and read through some of the product reviews and owner comments from various forums. Then I went to a local trusted dealer and looked at actual units. To be fair to myself, I looked at both TT's and 5ers.
I wasn't seeing THE FLOORPLAN in any of the used ones, but there was one new one that satisfied every one of my criteria - and that's what I bought.
In short, look at what you need inside. Look at where you're going to be going with the camper. Find floorplans that suit and decide based upon how well a trailer meets your list of needs.
Above all, don't rush the decision and as much as possible don't settle for something that doesn't quite meet your needs. Remember, choosing your trailer is part of the journey. Enjoy the process!