Upgrade to a T6?

The T6 is a great camera. The difference between the bottom of the market and the top of the market in terms of actual results is pretty small for most photographers these days (something few would ever admit). And you are correct, the XT is still a good camera, but there have been two significant improvements since that time that do affect the way I do photography. Current cameras (the T6 included) are capable of shooting at much higher ISO’s. This is allowing me to shoot at both lower light levels and deeper DOF than I could before. Current cameras are also producing great results at significantly higher pixel densities. This allows more cropping options and more reach. These two advancements are pretty big for my wildlife photography.  The T6 gets you most of what is available in these advancements. Everything else is pretty minor when you look at the ability of most photographers to achieve the results they want. It would be easy to get excited about a camera that has, for example, three times the frame rate as the T6, but no photographer will achieve 3 times the success. The difference in frame rate might be huge, but the difference in results isn’t. For myself, such a spec difference has negligible meaning. There is a lot of hype about equipment, especially at equipment websites like this one, but the T6 really is an excellent camera for most purposes.

You should really look for a T5 as they are being closed out right now. I saw one advertised for $150 recently. The differences between the T5 and T6 are pretty minor, but if you will use something like wifi, it is certainly worth the extra money. The T6 is a great value, but the closeouts on the T5 are a steal. There are occasionally some deals on the SL1 which is very similar in capabilities, but the ergonomics are considerably different, better in some ways, but worse in others. I personally like the T5/6 ergonomics better than my 5D3, although there are a couple flaws. If you are good with your XT, the T5/6 would be an easy transition. The SL1 would have you looking for the buttons.