22' 0r 25'? Does Size Matter?

Hello all and thank you in advance for any insight. Here is my quandary. I currently have a 2010 Nash 22h and an 07 5.9 cummins 2500. The trailer is great. 120w solar, super clean, and paid for! I have finally got a break from the real world and will be heading out in the spring of 2017 for a year plus trip. My family is my wife and I, our 22 month old, and our sweet but #110 dog. We have made quite a few local trips in the 22h and it has worked great. Tight but I'm grateful. But now that my son is mobile and I'm looking at an extended period in the trailer, I have started thinking about not wanting to have to put down the table in order for my son to be able to go to sleep. I don't really need to be convinced on more room, but I'm concerned about a larger trailer being a pain and limiting. If we went bigger it would more than likely be the Nash 25c as it really seems to be a great price point vs. quality trailer. Although I'm open to suggestions!
So here is the deal. Will a 25 limit me substantially more than the 22? My truck is the mega cab so it is long! We plan on driving cross country and are more of "off the beaten path" type of people, but we are realistic.
Any input from people who have done a longer trip would be greatly appreciated. Matt