Personally I dislike those test profiles a lot because they contain way too many test setup code than necessary, making tests hard to read/understand. They are also not very re-usable and if we use them a lot it is very hard to see what is set up in a test. It also slows down our tests because the entire test profile is applied to all our tests even though it is just needed for a single test.

Would you consider to refactor this test profile into test setup code? Only a couple of lines of Python code are needed to set up a fti/type that can be used to test the migration, without adding large chunks of XML to our configuration. See https://github.com/plone/plone.app.dexterity/blob/master/plone/app/dexterity/tests/discussion.txt#L11 for a starting point.