Realistic? Definitely. I'm starting my first tour this Thursday morning. If I can do it anyone can so get planning.
Every last drop of advice you'll ever need is covered in this forum (admittedly it takes a while to find it all), the Travelling Two book and site and general tinterweb.
Dunno about prevailing wind direction. I have a 20 mile loop I like to ride regularly but every time I do it, I somehow have a headwind on both the outbound and return journeys. Go figure.
“Twenty years from now you will be more disappointed by the things you didn’t do than by the ones you did do. Explore. Dream. Discover.” – Mark Twain