In RDBMS, it’s normal to have hundreds or thousands of tables in a database.
Where there are ways to increase the number of buckets in Couchbase, that’s not the recommended approach.
As @househippo suggested, you should design your document keys and queries so you can use a single bucket. We have customers with billions of documents in a single bucket.
I’ve written a bit of commentary on this in a blog:
https://blog.couchbase.com/couchbase-oracle-developers-part-3-database-objects/