Blender GUI with Mesh or Use Built in?

Iam looking for a way to - surprise - create an Blender GUI with some advanced things.
Since iam pretty new to blender and python and blender python i didn’t really know what to do.:eek:
It’d be awesome achieve something like this:

I know, some things would get really complicated so please tell me which ones’d be awful to create :eyebrowlift2:
Also iam wondering if this was easier to create in Blenders internel GUI “presets” or with an 2D Mesh-GUI in the 3D View.
I searched through half of the internet but i could only find half-helpfull things.:o

Every help is helpful!