Hi Ron: If you are happy with how the Canon DSLR camera and lenses feels in your hands, how you shoot, and are comfortable with the Canon menu system, then stay with Canon. You have a nice starter selection of lenses with the 50mm, the 24mm pancake, and 55-250mm telephoto. I have both the 50mm F1.8 and 24mm pancake lenses, and I love them. They are so small to toss into a daypack, or messenger bag to go shooting. If you are looking at a lens upgrade, I'd pick up something in a wide-to-telephoto, such as a Canon 24-105mm L lens, or an EF-S 18-135mm lens. I have a Canon EF 28-105mm lens that I always seem to go to first when I'm taking pictures. It is like my go-to, walk-around lens. Another potential lens upgrade for a crop camera body is the Canon EF-S 10-18mm ultrawide lens. It is an almost L quality lens, at a very good price. It is a great lens to take landscape photography, or even to move in closer for a different, slightly distorted perspective.
In terms of a second Canon camera body, there are a wide range of flavors, from new and used crop and full-frame bodies. Try to determine what you need for features and improvements in a second body--higher ISO, or faster frames-per-second, weather sealing, video capability, and then determine what you are willing to budget for a second camera body. Camera bodies often become obsolete after two or three years, when Canon and Nikon bring out their latest and greatest---better than all those older camera bodies. Of course, there may be nothing wrong with the older camera bodies, as they may still have plenty of life in them, and you can pick them up for a song--they just do not have all the latest and greatest features.
As with used camera equipment, there are a lot of good quality used lenses and camera bodies that you can pick up for less than a new equivalent. You just have to be careful at what you are looking at, what your photographic needs are, shop carefully and ask questions to the seller about the merchandise they are selling. Look at the customer reviews on eBay and Amazon on both the camera products and the seller. And it is not just cameras and lenses, but also tripods, camera bags, flashes, studio lighting--just about everything. Shop smart.