Hi Celina and welcome to the forum.
This is a great place to supplement your research so feel free to jump right in and post any questions you might have.
We have a 10' diesel pusher with a towed car so we don't even try to get into most National Parks and even State Parks are often limited.
I'm sure some of our members will be along soon to help you out with the pros and cons of "size". It sure is nice to be able to stretch out if it's going to be your home for six months at a time... but not at the expense of being able to stay where you want. You'll find that, like many things, it's all about trade offs.
Best of luck to you both.
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.
2007 Itasca Ellipse 40FD