I like cream cheese frosting because it's less sweet than vanilla frosting. Since you're adding sweetened coconut flakes and candy onto this, it can be cloyingly sweet if your frosting is too sweet. But, if you prefer vanilla or buttercream frosting, go with that. You just can't use chocolate frosting in these because you need to dye the coconut green to look like the Easter grass that you put in Easter baskets and you can't dye chocolate frosting.