Option C looks pretty sweet. I also like option D, but it doesn't have the sexy curves of option C.
As for built in subwoofers, I own some pretty sweet subwoofers already. When it comes to home theater bass, I prefer my sound to come from a stand-alone, self-powered subwoofer designed for as low of frequencies as possible. I've got three different powered subs in my home, one of which goes below 20 Hz and absolutely vibrates the entire room in JUST the perfect way.
Small speakers are great for bass if you are carrying a Bluetooth speaker, but not for a home theater (in my opinion). There ARE some smaller subwoofers that do an 'admiral' job, but they also cost quite a lot more in order to be decent.