Hi lyes,

> Interaction to draw a line you have to enter the sketch
> mode and select a plane and come out, to many process

Yeah, that kind of more formalized process with extra steps to specifically set up which plane you're drawing in is pretty normal with Mechanical CAD programs.

Another problem with it is not just extra steps but that you are not so free to just draw a line anywhere in 3D space that you might want it, for example in MoI you can go to the 3D view and draw in lines between any points that you want like this:





But that other kind of more formalized process is well suited for a different style of modeling, where you're more focused on having every aspect of the result controlled by specific dimensions and spacing from elements and stuff like that.

- Michael