Some points:

• Yield harvesting cannot occur here because nobody can simply short a UIA into existence.
• The problems of EBAs and max coin supply can be covered simply by requiring the dividends to exist before they are paid out.
• The problem of decimal places does not exist, due to the way amounts are handled internally. Payouts are always rounded (down) according to the number of decimals configured for the asset. Micro-payouts are rounded to zero.
• KISS. Coin-age and market-making incentives require statistics that we (currently) don't have, so you should leave them out of the proposal.