Seems like a very awkward idea.
I think it would be the easy way to organize my contacts.

Any reason you can't just assign the company to each of the contacts like
belong to that company? That's the way Outlook was designed and is the way
the rest of us would do it.
I'm different then.
Imagine that I work at Microsoft and only on my department there are a 100
contacts I want to add, on accounting another 100, etc... Imagine my contacts
list (huge) and the work will do to add them! On all 200 contacts, I'd have
to add address, phone number, accounting number etc... Then I'd have on each
of the contacts mobile numbers, email addresses, birthdays, whatever...
I think the easyest way would be create MIcrosoft as a Company CONTACT and
inside of each personal details for each of the members.

The other standard ways to group contacts is to use a Category or a separate
Contacts Subfolder. There is no such thing as "subcontact" since there is no
need for one.
Using categories seams kind of stupid solution. Each category for each
company would be impossible to deal with. If I'll have 100 companies, would
have 100 different categories... Not pratical
About creating Contacts subfolders would do if I could add TO THE SUBFOLDER
some information (the address, accounting number, data related to the company
itself) and then just would add Contacts inside with personal details of each.

My idea was to be able to do a "distribuition list" with data abnd insilde
contacts related to the "distribution list".
Or, easier, when I do "create new contact", despite of imput First and Last
name and Company, would input just Company and on "business address", imput
the address of the company etc... and be able to have tab to each related
user (person). On this tab, I'd imput personal details.

Is it a dumb idea? Am I just too complicated? Perhaps I want this more
simple.

Can't I create a form with this? Insert tabs like I want and relate the main
tab (company) with the other (persons)??

Best regards.
Deiota