Craigslist can sometimes be hit or miss depending on your area and where you are willing to go to look. As long as you like the bike and it inspires you to ride there is no need to upgrade unless something breaks or wears out. Also most shops offer some kind of service plan on top of the manufacturers warranty. If you find you are breaking spokes they might be able to build you a stronger wheel as a part swap or for a good discount.

As far as pedals go I have some Wellgo's on both of my bikes with Powergripps. As long as you wear the same stlye shoe minimal if any adjustment is needed.