What feature do you want to improve?
Doc counts for users are a permanent factor for performance, both server-side and client-side.
We store post-purging doc counts for when they replicate, but there is no visibility on the pre-purge doc counts, a number which impacts server performance.

Describe the improvement you'd like
When storing user doc counts, also store pre-purging doc counts.

https://github.com/medic/cht-core/blob/master/api/src/services/replication.js#L19