Don’t read the manual!
There are some truly bonkers plug-ins out there. We’ve all encountered certain effects whose sounds have baffled and amazed us and, even though we know we should read the manual to work out what exactly lies behind the utter sonic chaos, we’ve kind of dipped in and tried but it’s still not making any sense. These are often the instruments and collections we overlook but that’s partly because they make us feel baffled and guilty; neither of which are positive feelings when you’re in the process of trying to exert some control over your mixes. But try reframing your relationship with those dust-collecting instruments and sample packs by accepting that you might never get to the bottom of what they do. Instead, enjoy the randomness and mine it for hidden treasures.
If you find a library which self-generates sound from the moment you switch it on, or whose movement you can’t control whenever you hold down a sustained note, capture this sound as an audio file, having set it up to play for two to three minutes. Now it’s an audio file, you know what to do with it. You could find a small section you like and sample it to make it more playable. Or you could chop it up to layer the best bits of randomness with another synth or your percussive hits. Or you could run the whole thing as a sonic layer throughout your piece, but with a chain of effects controlling its tone, or volume, or pan position, or space within the mix or all of the above. Just because a library starts out by producing random sounds you don’t quite know how to control doesn’t mean you can’t impose the order you want through processes you are familiar with. Often rendering those sounds as audio files is a great place to start. If this idea appeals, libraries such as NI’s (Reaktor Ensemble) Skrewell are great, as are many of the other options within that plug-in. This is the tip of the iceberg though; many other plugins feature randomness at the front and centre.