The Cloudbees plugin provides the project level setup for each project (100+ projects) which paired with role matrix plugin allows us to give each team (team = project) self-service capability. From initial setup perspective, we configure the Bitbucket project, Jenkins multi-branch project and permissions for each team when a new project is requested. From that point forward, there is no need for Jenkins administrator to be involved with the teams day-to-day work of adding repos or configuring their build trigger requirements.
Without the ability to setup a project that will auto-detect repos/branches, there is a requirement for much more central involvement in regular upkeep of projects in Jenkins.
We do have the atlassian-bitbucket-plugin installed to our Jenkins environment as well to take advantage of some of the capabilities is offers like Build integration and rerun from Bitbucket UI. However this becomes confusing as there is overlap in functionality. Once the Atlassian plugin supports project scanning, we can consolidate back down to a single plugin to integrate Bitbucket and Jenkins.