Either a 172 or a Warrior are nice 3 person/4 seat airplanes.
The 172 has better visibility for sightseeing and has more headroom but is harder to preflight and fuel because of the high wing, and the Continental engine is susceptible to carb icing.
The Warrior is easier to preflight and fuel but the low wing blocks the view for sightseeing and the Lycoming engine rarely has carb ice problems.
You might also think about stretching the budget a bit and looking at a 182 or an Archer. (Or even a Dakota.) Even though I like the airplane I'd stay away from the Arrow and any retractable gear airplane in the low end ASEL category.
I like the thought about a good radio. Don't forget some ANR headsets with an iPod plug-in.
Good Luck.
CD