I’m sure single shot samples (not instruments) would be the most flexible all-around solution (especially if you are considering doing this for public release). Instruments would be a bonus and I added some quick notes on those below.
-Saving single hits as XRNI makes sense if you want to fine tune the sample with envelopes, fadeout parameters, or set NNA actions for example.
-Renoise XRNI supports layering hits with different velocities into layers. If you have soft/hard hits you might consider ordering them so. I’ve made some tools I’ve used to do some of the manual work involved, but they’re still “works in progress”. (Velocity layerer) (Grab sample keyzones)
-Renoise XRNI does not (yet…) support round-robin or random sample pool selection, so one can not yet do a snare that would automatically sound a little bit different on each hit.