4) That would certainly be beneficial. I think with a collective effort from all of us, Nexus most certainly will end up on other exchanges. Can you expand on what you mean by wallet services?
Wallet services such as SPV or thin-client development (also known as light-weight client) -- ie: mobile wallet infrastructure.
Also, web-wallets that act as thin client such as blockchain.info
Viz developed the node trust system with this in mind as it will help with the implementation of thin clients and mobile wallets. In fact we just recently discussed this again. That would be great if it is something you could contribute to.