I’ve just been trying exactly the same sort of thing using onset with these samples. As you say lots of fun here.
EDIT
I put in an entry, and just got an email to say that it was going to be played on BBC Radio 3 during the program ‘In Tune’ on Monday 14h Dec sometime between. 5pm-7pm (GMT) Created in Sonic Pi, with the aid of Audacity to trim silences at the beginning and end of the samples I used.
WOW it was great to hear my entry being played in Radio 3 last night.
It is here for 29 days(track 4) about 17:50 minutes into the broadcast.
I have uploaded my original to SoundCloud
I will see what I can do to publish the code later. However I did use SP 3.3beta as I wanted to utilise one of the new commands in it, so you need that version. although I have a temporary hack for two files in version 3.2.2 to get it to work there too.