That sandwich idea make me think, I really like it.
It can be done with heavy bottom cymbal and light-elastic top. Edge and bell switch can be made from that elastic top and steadily bottom but for bow can be used some hard material between cymbals in all bow circle area which transfer strokes directly to the bottom and piezo. Sufficiently elastic top cymbal will make switches easy done.
In this way all zones will have circular shape, like real cymbals. My English is bad but I hope that you know what I want to say.
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