Just came across this post. I think some kind of partnership with Railgun as @David_Heisenberg mentioned above would be awesome… If we could send shielded assets across chains once Zcash supports ZSA it would be a dream come true.
I actually heard about these Railgun guys a while back and made a post here… Railgun: Privacy when using DeFi possible ? (zk-SNARKs on ETH!?)
They just released an update and seem to be deploying on Arbitrum. With all the activity lately on there it sounds like a great move. Apparently they will be integrating with Gains Network to add private derivatives trading.