This could be neat for schools and absolute beginners I guess. But I think the "basic shapes + booleans" workflow is going to be much more annoying than "sketch + extrude" that you see in almost every other parametric CAD program.
To explain a bit more as "do your own kernel" is usually considered more mad than mad-science - this is not done on a whim. I spent over a decade doing CAD at Trimble, developing base tech and CAD offerings (including Tekla Structures and SketchUp). Happy to discuss the architecture more.
OpenCASCADE is included as part of STEP importer though.
Solvespace is a nice reference! One can already use it as prestep to modeling - just export the output as STL or SVG and import it :).
Sketching 2D shapes is a very natural way to start thinking about shapes.
That's why there is a sketch + extrude.
Here are few examples - 42 seconds to a desk organizer
https://www.youtube.com/watch?v=VX6g5slTdeE
Or quick wavy vase.
https://www.youtube.com/watch?v=IkhAUhlg81s
The booleans and extrusion shapes are complements - both fitting different type of modeling.
Booleans are not only about shaping but also about composing individual parts to more complex assemblies.
So one can extrude few parts, then eg. combine them with a join.
What CAD kernel are you using? OpenCASCADE?
The CAD kernel is written by me apart from the boolean solver for the meshes which is the superb https://github.com/elalish/manifold
To explain a bit more as "do your own kernel" is usually considered more mad than mad-science - this is not done on a whim. I spent over a decade doing CAD at Trimble, developing base tech and CAD offerings (including Tekla Structures and SketchUp). Happy to discuss the architecture more.
OpenCASCADE is included as part of STEP importer though.
Solvespace is a nice reference! One can already use it as prestep to modeling - just export the output as STL or SVG and import it :).