My very first cake

I took a class at church (not Wilton I, but using Wilton techniques) and decorating a cake was our "final". I tried to use most of the techniques we learned in class - it was fun! I made a chocolate cake with cookies n cream filling (from this site). I'd like to learn how to make my roses a little tighter and less ruffly, and to make my leaves end in a point, rather than forking. I'll also have to figure out this crumb coat thing, since I still got crumbs in my second coat of icing! Any suggestions?