Recommendation for additional unpitched percussion instruments

I am presently creating a percussion map and associated techniques for the Addictive Drums 2 library used in some jazz pieces I am working on. It works well. I can even pull in patterns directly from the plugin to the score.

Many drum kits have multiple crash (up to 6) and ride cymbals (up to 2). They can not really be put in the range high, medium-high, medium-low, low like the toms. Apart from those the kits also have up to 3 “variable instruments” (like bells, tambourine, electronic pads) which they call Flexi 1-3. All have their own dedicated techniques and midi note to activate them.

Does anyone have a good recommendation to set this up? New instruments or rather variants? Variants seems to have some limites I saw in the forum. I need the new instrument with 2-4 techniques.

I think I already mentioned this once but I still have not found a consistent standard for noteheads and stem direction for all instruments and techniques in a drum kit. Example how to notate a ride cymbal tip, bell, shaft and chocked hit. If anyone has a reference that would also be very welcome.