I recommend that you read the "sticky" at the top of this thread to learn basic information about pickup patterns, etc. The short version is an omni picks up 360 degrees of sound roughly evenly. A cardiod, as the name implies, has a pickup pattern that looks more like a heart, rejecting sound to its rear.
From your preferences it sounds like you want an omni mic, since that is the most "natural" sound and picks up exactly what you're hearing, and it picks up more room reflections and bass.
My experience with the D6 was that it attenuated bass somewhat, or at least, the recordings with omnidirectional mics had a more natural bass than they did when I moevd to DAT. However, I only ran the deck with one kind of mics. Others' experiences may vary.
It sounds like you should scroll down to "Retail Space," look at Church Audio's entries, and put in an order by sending him a PM on this site. There is no reason to buy from him on eBay since his prices here are better.