Versioning and publication for different nodetypes using CT module

Given a set of custom node-types:

[bulletin] > mgnl:content
[contentBlock] > mgnl:contentNode

where bulletins may contain 0...n contentBlocks (similar to mgnl:page vs. mgnl:component, or mgnl:composition vs. mgnl:block).
https://jira.magnolia-cms.com/secure/attachment/49049/jcrStructureExample.png

When publishing, by default, content-nodes (contentBlocks) are not published with their parent content (bulletin).

The configuration point to include custom nodetypes into publication process is "itemTypes" under the activation command. Include custom nodetypes using comma separated format without space.
See /modules/personalization-integration/commands/default/personalizationActivation@itemTypes=mgnl:contentNode,mgnl:componentVariants

From the restoreAllChildren action, one can set the flag RestorePreviousVersionCommand#parentNodeTypeOnly (in addition to #itemTypes), to false—which is otherwise to 'true' by default. See /modules/pages/apps/pages/subApps/browser/actions/restorePreviousVersion@parentNodeTypeOnly

Then it works with these itemTypes: mgnl:contentNode,mgnl:metaData,mgnl:resource,contentBlock

—

We need to recollect the rationale why parentNodeTypeOnly is true by default, and whether mgnl:contentNode could be present in itemTypes by default. (cc Roman Kovařík)
I expect the type-checks to be done with javax.jcr.Node#isNodeType, so there should be no need for additional configuration for custom sub-types.

Returns true if this node is of the specified primary node type or mixin type, or a subtype thereof.