Trying to change the driver log level appears to be impossible from the options object. It would be valuable to expose driver log level in mongo client options.

If mongo_client is created with options:
{ server: { loggerLevel: 'debug' }}
the options are swallowed at https://github.com/mongodb/node-mongodb-native/blob/2.1/lib/mongo_client.js#L260

A workaround is running the following line before initializing the driver, but it's a bit hackish:
require('mongodb-core/lib/connection/logger')('dummy',

);