Ok,
I am now pretty happy of the state of this addon to provide a download link for people who may want to give it a try.
I have uploaded the files to WoWInterface under the name "Sigma ProfessionFilter".
You can find it there as soon as it is approved.
Or just go to the
github repo.
In this phase, getting as much feedback as possible is critical for getting things right.
Thanks a lot to anyone who will take the time to give this a try.
these are some screenshots: