move to the country

So, we are debating whether to renovate our 3 bedroom house, move to an existing larger house, or build our dream home on at least several acres of land, preferably on water, a river or lake.
It’s a tough decision, since we are just 6 years from paying off our mortgage, and then wow, all the things we could save for (college, vacations, retirement, etc). But we have outgrown our 3 bedroom house….. Do we really want to be house poor and have a 30 year mortgage???