OK, I'm a younger female in your age range, so just my thoughts from my perspective:
-What would be the plan when your baby gets a bit bigger and starts moving around? It's all fun and games when the baby is little, because you set them down and they don't go anywhere. Once they are able to start moving around, they want to MOVE, and that's not that possible in a motorhome of the size you mention, especially if half your off time is spent driving (during which time your baby should be in a carseat).
-Old Biscuit asked this same question but, what will your wife do when you're off working? Just hang out in the same 240 sq ft you're travelling in? I know I wouldn't like that too much.
-What would the plan be if you had bad weather? You, your wife, the now mobile baby, and 3 dogs would be cooped up in that motorhome and you would probably be hating life.
-What would be your plan if you rented your house out, and the tenants quit paying rent and you had to go through the eviction process?
-What about your wife's job? Say she quits the job to do this (which sounds like your dream), and then has difficulty finding a new job when you come back to regular life?
-I can't remember if someone asked this or not, but where do you plan on parking this motorhome while you're working? I'd assume you'd want full hookups, and those places, especially in populated areas, don't come cheap.
-We have 3 dogs that I love to death. I don't even like camping with them that much, so I can't imagine having to LIVE with them in our trailer.