There might be a log somewhere but most of the other strings get updated on existing installs.
Not exactly, eos-packagelist can show you the current packages being used but I don’t think it is wise to blindly install that list each time.
No
The conceptual problem may be that the “releases” aren’t new releases of the distro, they are new ISOs which may or may not have a different default set of software.
Rolling means that the software you have installed is constantly updated. It doesn’t mean that software from future ISOs are added. Most people would not want us to modify their existing system because we changed the defaults on the ISO.