The Antec Sonata III is not a very popular pc case with gamers and ehtusiasts. It is designed for those who want a quiet pc. That's why it only comes with one case fan. The other problem is the front bezel. The bottom front would restrict airflow if a fan were installed in the bottom front of the case. In addition, the case configuration is not ideal for adding additional intake and exhaust fans.
I've looked at the Antec 200 and like what I've seen. It's actually pretty similar to the 300, but has a bit different styling, a hot-swap bay, and I believe a fan filter (which you can remove). I have the 900 and 300 and like them both, but would build in a 200 as well.