Thank you for sharing this model with the community.
As far as I can say, this is correct, but I would just add "end events", describing the state of the process after the last "finishing" activities.
I was thinking: What if some document was passed from one person to the next as part of the the process - how would you model that? As output from one activity and input to the next or as output of one role and input to the next role, or something different?
if you model e.g. an epc, you model the flow of the activities. The handling of documents - or data, generally spoken - is models implicitly via the connection to the activities. Thus, you model, who is doing what, which which data.
See this example from the demo process.
Here, a user group (accounts department) produces output data (which could also be modeled as a document but is modeled as database here) by "sending the order confirmation".