L'espion Noir,
I think you noticing what you DON'T like about CDs is a good step in determining what you DO like about one. I can't imagine there being one fast rule about what to use, if you like the "color" of a CD, then use it as your reference if it's applicable (in your opinion, of course). Maybe the Jeru CD is really sonically phat-as-hell to you, save the overall volume. If so, then you can still use it as a reference CD just make the necessary adjustments in the overall volume of your product. Think about it, if you (for example) like the sound of the Wu's stuff, then Master P isn't the thing to use for a reference CD, unless there's a particular element of P's stuff that you want to capture. Conversely, if you wanna do some west coast stuff, then Primo's beats ain't what you should be listening to for reference (unless you feel you got a reason to).
<an aside, but it relates the same point, I think>
How did I pick a mastering engineer? Well... I found a guy who was mastering stuff that I was listening to and went with him. I send some other things I do to a different mastering engineer. Now i'm pretty sure either could effectively master any type of material, but I know for sure what these cats each do with certain styles of music, and most importantly, it sounds good to my ears. Maybe i'm just making myself jump through unnecessary hoops, but at least I'm nobody's fool but my own.
Did that help or was it just a bunch of nothing?
Flo' Dolo