I'm a beginner playing around with shooting various things: landscapes, flowers and insects, and loads of action shots of my three very active preschoolers. Currently, I have a 18-55 IS, a 55-250 IS, and a "nifty fifty", all pretty basic... And now I'm curious about trying something else I'm too much of a beginner to upgrade in quality of lenses - wouldn't know the difference just yet! But I'd like to maybe try another prime for portraits, like the 100mm macro. Or, I've also looked at Canon's 70-300mm... but that one seems hardly worth since I already have the 55-250. Ideas? What would you add to a pretty basic beginner's kit to get a bit more versatility?