You'll probably need annual chain replacements, other than that, it should be pretty minimal.
Gearing-wise, I'd probably go with the 44T or the 42T, if it's a hilly area. I'm assuming you have the stock 7-speed drivetrain. With a 14T small cog, your top speed is pretty limited unless you go with a pretty big cog.
If you're into projects and upgrades, upgrading to a 9-speed drivetrain would be a big benefit. You can easily get 11-32 cassettes (assuming it's not a freehub), and that would give you significantly more low and high end.