For point ,: you're correct in that we (as in the crypto community in general) have yet to come up with good on-chain governance mechanisms, so its likely that robust decentralized governance systems are at least a few years away.
Underwriting is a heavily regulated process in most countries with licensing requirements. You could claim that you do not underwrite yourself,so don't fall under regulatory purview. Interestingly your model will fall under the P2P regulations of India and China - where there are specific models where the marketplace does not underwrite, but risk is assumed by lender. Or - you have to make sure that the underwriters are regulated entities.
P.S. I run a lending startup in India. We primarily look at the Blockchain as a means to solve the credit history problem in India.