Many of you have expressed interest in potentially switching to a mirrorless camera. Having been through that process myself, I know there is a lot to consider. To help with your decision, here is how I would recommend moving forward.
1) Research the following cameras to see what's the best fit for your photographic needs. All of these models are under $900 and offer professional image quality with advanced features. In no particular order:
Panasonic GX 85
Olympus OM-D EM10MKIII
Keep in mind, each of these manufacturers offers a wide variety of bodies and lenses so explore their entire line of products. Remember, even more important than the actual camera you choose is the selection of lenses. Now, I'll probably take some heat for this statement, but here it is. Sony makes phenomenal cameras, but their lens choices are severely lacking. Also note, Olympus and Panasonic share lenses so you have a huge selection with either of those companies. Finally, Fuji cameras do have a larger APS-C sensor which will offer slightly improved ISO sensitivity. As a trade off however, the gear is bigger and heavier.
2) Consider selling your current gear over at keh.com. They offer the best prices and you can get an online quote for what they will pay you instantly. Alternatively, you can look at selling over at Adorama.com or bhphotovideo.com. All of these are safer options than eBay or Craigslist.
3) While we all love new gear, think about buying something in gently used condition from one of the above stores. You will save a substantial amount of money and often receive a warranty from the seller. This will allow you to invest in better lenses, necessary filters (polarizer) and a new smaller camera bag.