Hi stefano,

re:
> could you consider the concept of a "master hole" whereby if a hole object created
> or duplicated a user can later on change the single master hole diameter to change
> all such hole sizes..

One method that could work for this already within current capabilities would be to assign a name to the hole's face or edge object.

After the name has been set there will be an entry for it in the "Objects" section of the Scene Browser and you can go there to select all of the hole geometry with one click.

One issue that could complicate that is that when an object is contained inside of a group the name only shows up as a child of the group instead of showing at the top level. Maybe that could be solved by having an option that you could set on objects for having the name appear at the top level or inside of the parent group...

- Michael