I added a few suggestion that came out from the comments in the OP.
I also corrected some embarrassing typos (I love "tinkering", not "thinking"!)
Hopefully, more valuable content will continue to come!
No, I didn't added the Etna suggestion, yet.
@fillippone this is truly one amazing megapost and you even provided videos for lazy people (cool music but I expected something more Italian).
Can you please tell me about material that is used for making Hermetic container?
I have seen few of these before on aliexpress and ebay but I think most of them were cheap and made from aluminum if I remember correctly.
It would add to structural integrity a lot if this could also be made from stainless steel.
Also your Italian videos are coming later.
The container is in a very light aluminium.
Not more structural stiffness is needed, as per
Jameson Lopp test. Also, in case of levate temperature, aluminium could be easily removed, without transforming the washers + case in an unmanageable blob of metal.