Do you need a custom BPMN Symbol palette?
Then this is the right plugin for you. By default we removed the pool, data objects and the complex gateway from the modeler, but you can extend the plugin and remove more symbols that you don't need.
Put this directory into the plugins
directory of the Camunda Modeler and you're ready to go.
If you're interested in how to create your own plugins see the documentation and this example.