Hi Bernd,
Thanks a lot for your kind words!
I actually don’t use a lot of Addons, but I do have Hardops and Boxcutter and they are fantastic, (and have life-long support and updates, so worth the money), but I’m not sure they’ll help with these specific problems…. I also hear great things about MeshMachine from someone whose opinion I trust (and who knows a lot about Addons from using them and writing them),