Well if you already have Postgres then yes, sounds fine. I don't really agree that SQLite needs tons of tweaking -- setting journal_mode to WAL/WAL2 is the only real thing worth doing, everything else I would consider optional.
Version upgrades for SQLite are basically a no-op though, that's kinda one of the reasons why it's so great to run in production (and deployment a maintenance being mostly a no-op as well, apart from setting up backups I guess).
I don't actually suggest that everyone should run their production on SQLite, but it's genuinely worth considering especially for small-ish projects.
Foreign key constraints, sync frequency, busy timeout, strict typing on tables, explicit types for integer primary keys, and a convention for storing dates and times are others I would want to do up front.
I set it to enforce foreign key constraint as well.