I would love that Perhaps something like the regular scout reports, only custom made?
I cannot think of any way around the copy-pasting myself either. :/ Indirik is right.
Well, something we've had in mind for some time is a way to get scout reports out of the message body: instead, they'd show up as separate links below the message.
We'd need to evaluate whether it's a) worth it and b) not abusable, but it might be worthwhile to do something similar with actual messages, as well.
Obviously this wouldn't solve the problem of copying & pasting unit reports (ick) or the results of actions ("Your men work for X hours", etc), but it would at least start to address the problems.