You should definitely check out Jenkins Job Builder - http://docs.openstack.org/infra/jenkins-job-builder/. It lets you store job configs as nice yaml files which can be checked in to version control. It's what openstack uses to manage jobs for the many many openstack projects. I've been using for a year or so at work and highly recommend it.
I'm not in charge of writing the jobs, just standing it up and migrating a few dozen teams onto the system. Some are migrating from previous Jenkins systems, so the majority have old jobs in config.xml files. The Job Builder makes everything a little bit better, I've seen a few people using it already.
I'd still never use Jenkins on my own though, I'd just use Drone or pay CircleCI.
