Thanks everyone for the various comments, suggestions and tips !
Marissa... Yes... That would be very important to have something in the future that could address the direct creation of Spaces (considering it's importance inside BIM modeling... if there are nodes to create Walls and Slabs... that should be also ones to create spaces objects ...).
Don, the usage of "Create Custom Object Path" is a great tip indeed... thanks !
Again, thanks also Alan and MaWi for helping !