I don't see a particular problem with it, so long as the finances work. As you'll discover here and in the Flying Instructors' forum, pay isn't great as an FI unless you can get into one of the big schools, and even then it's not wonderful, but it can be a very satisfying way to make your living. You may have to go through some pain to get there, but if it's what you want then go for it!
Scroggs