There's a lesson to be learned from all this...

DON'T CLOSE OFF YOUR ARRANGER! Ketron, Yamaha, are you listening?

If you are going to go down this audio loop road, there's basically NO WAY you can anticipate what grooves and rhythms and styles your users need. So, making it EASY for users to put their own grooves in is part of the decision to go down this non-traditional arranger route.

Otherwise, you end up having a 'potentially' great feature that, in practice, turns out to be only for those who are content with the factory audio styles (and content that anything they want that isn't in there will sound poor in comparison). In Yamaha's case this means all that effort spent on a mere 10% of the content. This route, to change completely how you have done drum tracks after decades of MIDI kits, is basically an 'all or nothing' trap.

If the audio styles don't utterly blow the MIDI ones away, what's the point? And if they DO, all the styles need audio drums. And that's where allowing 3rd party style makers and technically savvy users access to the tools to be able to make THEIR OWN! Because you, to be honest, don't have the time or money to flood your users with the myriad different needs they all have, from Balkan folk/pop musics to crunk to zydeco. You can't do it all... let US do the rest!