Great idea although too pricey for what you get IMHO. I'll stick to hacking Kindles for now.
Of course, you can skip the server section and make the IP address point to your local server. Some caveats are you need to use pngcrush to turn the image into a format that the kindle can use.
Link to GitHub: https://github.com/yoonsikp/weather-display
Everything I read about hacking older Kindles involved rooting them and displaying a HTML with whatever you wanted. That sounds too easy, and I'd like to go deeper.