If you are only going to use AutoCAD and RevIT then I would save the moolah and go with an Ryzen 5/7 or CFL i5/i7 with a standard GPU. AutoCAD uses more CPU than GPU and uses DirectX and not OpenGL, which is why you can use AutoCAD on most 'normal' computers.
However, I've seen workstation towers and laptops age very well. So if you are going to hang on to it without replacing it soon, then you have that.
How much of detailed work are you doing with AutoCAD? Are you 3D modeling in large assemblies or just 2D work?
Edit: On my 3 design/engineering jobs, I've always had Xeon with Quadro. This is a must for SolidWorks and the like, but in the cases when AutoCAD is used, the computers were usually overkill for AutoCAD only tasks.