As far as getting the most out of this or any other music software, I find that it helps to think of the program as an instrument such as an organ or synthesizer with hundreds or thousands of presets. I say this because I know of no other way to know what you have your hands on other than to invest time in listening.
This can be frustrating if your goal is to quickly crank out an arrangement. However, I know of no instrument or software which is worth using which does not require some learning. Yes, it does take a considerable amount of time. In the case of BIAB/RB, many tracks rule themselves out because of their obvious unsuitability. You are not going to be using a metal guitar in a jazz trio. That still leaves numerous (to put it mildly) choices.
My solution is twofold. First, I just get into the process. Every new iteration of BIAB is a gift--one which takes time to open. Enjoy it! I had to do this in order to use Acid, listening through at many classes of loops, if not each individual file, to know what I had my hands on. Same with my Roland JV-1010 synth module. Knowing that you have a patch named "Ethereal Pad" doesn't really tell you anything. You just have to listen.
The second thing is this. (I work differently from almost anyone here, so this applies to almost no one.) I have virtually given up getting BIAB to do what I want it to. Instead, I use it for inspiration. I got tired of being distracted from creating a song (usually a cover, which I have given up on anyway) and passing up on all the great ideas suggested by BIAB. If I didn't know that I don't have to, I'd list BIAB as a co-composer on many of my works. I end up with a bunch of cool stuff that I never would have thought of on my own. (Obviously the Good Doctor had this in mind when creating the program, so I have to thank him for yet another stroke of brilliance.

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But given that you have a fixed idea in mind when you sit down, it looks to me like you have a choice. Either take the time to thoughtfully peruse the palette of sounds and styles available, or resign yourself to getting close--but no more--on your arrangements. Of course, you can ask questions here, and I suggest that you do. But that won't make up for discovering on your own what your new 'instrument' has to offer.
HTH,
Richard