Hi.
3ish fsms is about my minimum on characters and AI
I don't think that it is a good strategy for this case, but i never tested it.
But creating things @ runtime in most cases is not a good thing.
i would rather go with using templates.
And depending on the project :
Have different fsms that can be enabled/disabled on an object.
and/or
Have a few version object for different AI behaviour.
and/or
Feed certain data to manipulate the actions/states inside the templates.
(for example with weapon classes /damage)