For now, every process definition can have its own terminology, patterns, specifications and the like. It would be nice if a business process designer would have a set of standardized specs he could start with. Some examples:
- a formal set of transitions that may be used (e.g. so there will be only one "true"/"false" transition set, and not a "yes/no", "go/nogo", etc. if they mean the same)
- a transition always having the same actionHandler
- a swimlane definition together with its assignment handler (e.g. now it is possible to have a "manager" swimlane and use an assignment handler not relevant for that swimlane)
- a node with two actions
- a tasknode with 3 tasks
- ...
These could be specified in some er... specification file that could be versioned as well. These specs could have a name or an id. They could be referenced from the process definitions by id.
A constraint could be used that elements cannot reference specs that are other elements (e.g. a transition cannot reference a node specification)

I know, a lot of feature requests, but I saw this already in a FWFF (Friendly WorkFlow Framework :-))