The component set in Flash has always left a little to be desired. First introduced as “smart clips” and then later as componenets they have always been a little bloated for my taste. I’ve been using Bit Components for years and have seen great file size reductions in my AS2 projects.
Recently, I’ve noticed some really great AS3 component sets popping up like MinimalComps by Flash guru (and former Brightcove employee Keith Peters) and Bumpslide. While Minimal comps is AS3 only, Bumpslide is AS2 and AS3 and extends the MinimalComps classes. Check them out!