Eventually, the bigger the pool, the more effective its protection, as explained in Namada’s mission: The Namada mission.
First, we can measure the percentage of cryptocurrency tokens (by relative market capitalization) that are shielded at rest. This includes, for example, shielded assets on Zcash, Namada, Penumbra, Aleo , Anoma , Aztec , etc. - any well-designed shielded pool counts. Privacy is created by assets shielded at rest, so by and large, more assets shielded at rest means more privacy available for users. We should also measure technical stability: are assets that are shielded remaining secure, or are there incidents of them being drained in exploits?
Conversely, a small pool offers less protection.
- The transaction size could be capped at a certain percentage of the pool size.
- Also, transaction sizes should not be idiosyncratic, but a few preset amounts.