You can change the autovacuum scale factor for an individual table:
ALTER TABLE tab SET (autovacuum_vacuum_scale_factor = 0.01);
VACUUM is not cheap, so running it more often will take more resources. However, since
VACUUM typically has less work to do when called more frequently, it is not as bad as it seems. The main overhead is that each
VACUUM run will scan all indexes on the table, and that work does not become less if you run
VACUUM more often (although PostgreSQL v14 has introduced an optimization that skips index scans if only very few index entries have to be deleted).
Normally, it is fine to have the standard 20% of bloat even for large tables. Consider increasing the frequency only if you are aiming at efficient index-only scans on that table.
The main thing you should watch out for is that autovacuum is fast enough on your large tables. For that, tune
maintenance_work_mem to be high (so that the indexes don't have to be scanned more often than necessary) and maybe reduce
autovacuum_vacuum_cost_delay on those tables.