The only fact type, where verbalizing role names would help (that I can think of), is the recursive form (is there a better name for types where one Object plays both sides of a pedicate?) - so far, those are the only role names I (actually either your or Matt's suggestion), found it helps to to explicitly name roles.
What might help is a warning issued when recursive fact type roles haven't been explictly named. Along the lines of the need to set a datatype; as that help avoid problems closer to physical implementation.
Verbalization of all roles, only as a toggled option.