The first question I'd ask is, what is the business problem you're trying to solve?
The second question I have is - are these groups performing largely the same function? I don't think you can really compare transactional scores unless it's a very similar function; for example, if the groups were the call center reps under each individual supervisor in the center, and the transactions are customer support calls or sales calls. Trying to compare a software engineering group with a financial analyst group in terms of transactional scores is never going to work out - the nature of the transactions and the metrics is far too different.
It's easier to make score comparisons across diverse groups if you have relationship scores, because those are easier to make consistent across groups. Even then there are caveats - a low score is about the relationship, not necessarily the group itself.
I think the best way to integrate diverse metrics is to not do it. At least not analytically. For any business, you have your business strategy and have somehow developed some faith (vision of business leaders, demonstrated analytically, etc.) that certain actions will help you achieve that strategy. Once you have organizational buy-in that something is important, go ahead and measure and report on that thing. If you are solving for reporting up to a higher level of management that doesn't want that level of detail, I think the correct approach is not to try to integrate datapoints that resist integration, but to report at a more abstract level. Report on progress against the strategy and give visibility into how the operating groups are using the transactional metrics, with the opportunity to dive deeper if they are interested.
The "Balanced Scorecard" approach is something I hear talked about in professional groups, although I've never seen it implemented. You can find more information here: http://www.balancedscorecard.org/BSCResources/AbouttheBalancedScorecard/tabid/55/Default.aspx
Hope this helps. Please comment if you're able to add some more information about the business problem you're trying to solve.