We have a 45' motorhome and own a trailer that is 30' overall and has a 26' box. I have used it to haul a car and 2 motorcycles. I have taken it around the country. I don't use it to haul stuff anymore because it was too much of a pain. It wasn't so bad in the midwest and west. I found sites to be larger there and fewer trees. It was worst in the northeast and mid atlantic. If the site was long enough a tree was in the way.
If I had to do it over again I'd first eliminate my extended tongue and also about 2' from the box. This would shorten the trailer by about 3.5'.
We have lots of friends that very successfully use large trailers. But generally they are going from up north in the summer to down south in the winter with stops in rest areas on the way down and back. The problem comes when you want to go other places with it.