The UMA protocol, while an improvement over the Synthetix protocol in a technical sense, its complexity and liabilities leave much to be desired.
The UMA protocols relies on specific "token sponsors" in their ecosystem who manage a whitelisting processes, the creation and sale of tokens, and the initial collateralization. They also require using their own unique oracles rather than something secured and tested like Chainlink.
Finally, they have a dispute resolution method tied to the oracle process. While this may make sense for betting market oracles like Augur, having all protocol assets able to be over turned by human interest arbitration defeats the point of using cryptocurrencies at all.