I am basically in agreement with Seignorage shares, but I have one major objection.
The system described in the paper explains how to control the exchange rate.
Indeed, this is the system of exchange rate control I recommend nubits adopt.
However, the paper says nothing about the reserve ratio, or how it can be controlled.
Seignorage shares will be highly unstable if the amount of value in the stable asset is large relative to the amount of value in the volatile asset. Essentially, the system design leaves long-term stability up to chance. If you had a major downturn (like we have often see in bitcoin), the whole system could explode.
You need to have an additional monetary policy instrument such as the interest rate and/or txn fees to control both the reserve ratio and the exchange rate simultaneously. Once you have this in place, you can prevent accumulation of excess debt following a downturn. Seignorage shares ignores this problem completely.
Note: there is nothing new in Sims’ paper. Search the bitcointalk forum and you’ll find that all the material in the paper has been discussed before by multiple people. It’s just that people only became interested in these concepts over the last 6 months or so.