Hi zroadhouse,
If I were to ask you a few simple questions [One's that I asked myself when I finally decided that sleeping in the back of a Blazer just wasn't going to work for me any more] that are really for you to answer to yourself, they would be:
1) What do you really want out of the trailer?
2) Is a large heavy CT/Toy-Hauler really necessary for the toys you plan to haul or is it something you want?
3) How much time are you going to be spending on the road in the trailer?
4) Is the larger trailer to help reduce "cabin-fever" or will an awning open an "outdoor room" that will work?
5) Where are you going to use the trailer (on the highway, camping off the beaten road [some dirt roads, but not 4X4 roads), away from the crowds (off the beaten path (4X4 may be required)?
6) Will you be alone, or are others going with you -- Wife, kids, friends, etc.?
7) ??
This list goes on and on and is limited only by the trailer buyer ... I do not want to make this complicated because it really isn't, as you can add and change the add-on's but trailer size, construction, and quality are pretty much built in from the ground up. Using some kind of Pro & Con list (or a Force-Field Analysis as they call it in the business world) can help you decide on what you really want/need for the time, effort, and $$ spent
For example, I really like the room provided by a longer trailer (12 or even a 14 footer), but as I decided on the actual use for the trailer and started my Pro and Con list, I came up with a maximum size of 6X10 with a taller roof and a short tongue (3' max). I do not have an ATV as of yet, but I planned Murphy-style cots that will allow room for a single (straddle-type) ATV, if I want to add one later. I started out with a pretty good and heavy built full-size 4X4 to pull with; with that said, I over looked several thing: the trailer turned out heavier than expected at about 1,400 lbs. dry (before I started adding to it), truck gearing was way off _ I need to rear-gear both the front and rear diff's (4X4), this cost over $1,200, and the taller trailer (jacked up for off-road high clearance and 6-1/2 foot ceiling), along with a fairly flat fronted trailer has now created a heck of a wind dam at highway speeds (more $$ out for a roof rack and wind deflector [I hope it works as well as the theory calculates] .. all this adds to changes that were not difficult, but cost [over $2,000] that was not planned in the beginning. I recently purchased a house in Minnesota but, being a retired Desert Rat that loves the hot weather, I anticipate lots of time on the road and already have put over 2,500 miles on the trailer at an average of 7 mpg ... I am really hoping that the re-gearing and deflector help me get a little back on those investments [I will be heading out for Min sometime in the next few weeks]!

I apologize if I sound negative, I do not mean to, I am just trying to throw some questions/ideas out for thought that maybe will reduce your trial and error path a bit, but then again, trial and error is good_I suppose it is how we learn the best (if we never made hockey pucks for biscuits, we have never learned to kneed less). I love camping, hate crowds, love the outdoors, love this country, love my trailer, although it is not perfect ... yet, AND
I sincerely hope you find the right vehicle/trailer that will make you happy, because really, that is what it is all about! 