Hi Allison,
Welcome to PPRuNe.
I think you'll find that good an aircraft as a Navion is, they're getting a little old to be appreciated for the good aircraft that they are. I've never heard anything bad said about them, just that such an aircraft would become a labour of love from a maintenance standpoint. They were designed in an era when "heavy and tough" were good, now it's more "light and economical". Some of the Navions are equpped with engine models which are not so well supported any more.
I think the Navion may not be your best choice for the next plane, as it sounds like you have other interests. Enjoy the C172, and maybe aim at a Cardinal, 182 or 210, they're better known...
Cheers, Pilot DAR