I'd really love some kind of distributed-for-performance database using the exact optimizer and query planner of SQLite plus std plugins (FTS5, JSON, transitive_closure, spatial). Something like a mix between Bloomberg's comdb2 (which uses a modified SQLite frontend) and rqlite (distributed-for-safety).
Note: You can save most of the shortcomings of CDB on the SQL client side today, but don't underestimate the time it takes to implement CDB-specific workarounds...
Why do you think the identical optimizer and query planner would work in a distributed environment, with no changes from the single server implementations?
If Comdb2 7 ever reaches stable, and BLP invests some time into deployment, ops and monitoring tools/docs, it'll be a strong competitor.