Hey there,
I have another suggestion:
How about changes in the changelog. I don't mean this Changelog: "Ticket X closed by X (reason)" I mean this: (example) Changes in 1.1:
XXX
XXX
XXX
= Added
= Deleted
= Changed / Updated
You can define this in an extra field (like severity, assign to, etc.).
Would be very nice to see that :)
Here's an idea I had for the new Change Log page.
And to add custom lines, there will be a change log box on the edit milestone page.