I'm going to attempt to answer this.
While I have never had to do this in Ansible, I believe what you propose is doable. Is it easy? That's a different story. :)
The module you found uses the Python library bigsuds to manage the F5. This makes use of the F5's iControl SOAP API. It seems all actions for any F5 module in the extras repo uses local_action which simply has the module hitting the appropriate functions in the SOAP API.
You will most likely need to write your own module to perform the actions you are hoping to perform. That would be written in Python and can be easily dropped in. Just model your own after the existing F5 modules in core.
The way I would approach this is to first determine if the iControl SOAP API supports the functionality you desire, i.e. creation of the UCS file, commands you wish to execute via tmsh, etc. If it does, then map out what a playbook might look like and figure out what all you need in your module(s).
Not sure if that helps, but it's my 2 cents. :)
-matt