No problem, happy to help :-)

The thing is, with that command, you get *all* the installed packages.
That includes all the packages in the base install plus any dependencies
installed along with the packages you installed later.

Any packages in the list that are already installed as part of the base
system should just be ignored. The thing that worries me is if you have
any packages in the list that aren't in the repos for the new version
(particularly libraries), whether or not the reinstall process would
fall down (I don't know whether it would, I've never used this way of
doing what you want, but I suspect that it might) in which case, a
little judicious manual pruning of the list might well be in order -
don't worry about deleting any dependencies for the packages you want,
dpkg should be intelligent enough to pull them down from the server for you.