A lot of people ask, "What kind of icing do you recommend if I'm making my own cupcakes?" My standard answer is: "Whatever kind of icing is your favorite." And it's true. As long as you put your fondant decorations on right before a party, whatever icing you use does not really matter.
That said, do I have my favorites? Heck yes. I happen to not really care for super sweet, powdered sugar-based icing. This is just a personal preference, and I do use it occasionally based on the event, cupcakes, guests, etc.
But for those of you that are wondering what my favorite icing is: it's Italian Buttercream. It is a cooked icing, so it does take a little longer to make, but it is totally worth it. It is much more stable, and holds up very well on your dessert table while your guests are enjoying the party.
The best recipe I have found is from the Culinary Institute of America.
Give it a try (and some patience--it can take some getting used to), and I think you'll love it!