Allow users to change common database server settings

Your Support staff would know better than I do, but I would imagine that certain MySQL (MariaDB) setting changes are requested quite regularly.  For example:

character_set_server, collation_server
max_connections

default_storage_engine

long_query_time / slow_query_log / slow_query_log_file

And so on.  This would give webmasters greater control over their database servers, and reduce the time that is spent by Support on making these minor changes.