I don't have any off the top of my head, but a mid level case instead of a micro or mini. I would say that if you bump the budget up to 60, you will get much better airflow out of your case. Airflow is most definitely what you want, and depending on where you live and the temperature (if it's cold enough), you might be ok with the one you have there.

A quick search turned up this:

http://www.amazon.com/Sentey%C2%AE-Computer-Transparent-Removable-Management/dp/B00MNSDBVW/ref=sr_1_6?s=pc&ie=UTF8&qid=1413040827&sr=1-6&keywords=computer+case

http://www.amazon.com/Sentey%C2%AE-Gs-6006-Z-tron-Gaming-Computer/dp/B00MNSIR66/ref=sr_1_7?s=pc&ie=UTF8&qid=1413040827&sr=1-7&keywords=computer+case

http://www.amazon.com/Azza-SIRIUS-CSAZ-206S-Tower-Computer/dp/B00LX9T7QU/ref=sr_1_10?s=pc&ie=UTF8&qid=1413040827&sr=1-10&keywords=computer+case

http://www.amazon.com/Corsair-Carbide-Windowed-Computer-CC-9011017-WW/dp/B008B6ONXA/ref=sr_1_17?s=pc&ie=UTF8&qid=1413040827&sr=1-17&keywords=computer+case