Welcome back to the world's greatest sport. For myself, I like a road bike with a somewhat relaxed geometry and enough clearance for 700Cx28 or perhaps even 700Cx32 tires. This is one reason I am so fond of the old steel classics. Also, make sure you get low enough gearing for grades, headwinds, and fatigue you anticipate. Many of today's high performance bikes have very tight gearing and very tight geometries, neither of which suit my needs.