Thanks for the reply, I'm going to see if that fits our approach too.
I went ahead and bought the Ultimate single license edition, if for nothing more than proving or disproving EA is a good tool for BPMN 2.0 and BRs. I have also installed the BPMN 2.0 add-in to see what in addition to the Corporate install it provides.
After reviewing the above link provided by RoyC, I do see value in producing a business rule database, BUT how to then interact with them is what I will be investigating and building on. Others on the projects feel/think there is little value in producing a domain model for a COTS solution, so I think that approach is for us outdated.
We are NOT designing and building software and code, just ensuring that a COTS solution covers all business needs and identifying gaps where it falls short, including business rules. For the one application I am currently assigned to, a very early initial analysis shows there are very few BRs and most are controlled manually through human experience, knowledge, activities and tasks, and not automation.
As more and more software development companies move away from monolithic predefined solutions and products, i.e. one-size-fits-all, to a Lego building blocks of modules, heavily customizable, it will have an impact on tools such as EA. Will Sparx and EA keep up is the question.