At first I was like 2.5 axis? What good is half an axis? Then I realized this was related to 3D printing and laser cutting. AH, that makes sense. In this context, the half an axis control is the 3D printer's waterline. The waterline only increments once per layer of print, and it increments by the thickness of the deposition layer.
This is a nice tool to add to Onshape for prototyping. There are other CAM plugins for generating gcode from Onshape models, but they are pretty much export tools to move models into desktop software. So Kiri:Moto is pretty cool because the toolpaths are generated right in Onshape.
Besides CAM, the other thing I'd like to do with Onshape models is FEA (finite element analysis).
Good 3D CAD can get pricey. Good desktop FEA software is expensive, and for a good reason. It's expensive to develop! These are not simple problems to solve. They took decades of research and refinement to get where they are now. At the time of this writing, it is still not possible to automatically generate optimal 5-axis tool paths. It's a complex problem!
If you're a small shop or one man operation without the big $$ to purchase a $10k software license for a desktop machine, there are some newer options that are going to become very popular. Cloud based services can sell you compute time by the hour.
Fidesys has a new simulation plugin for Onshape that looks like it would suit the needs of a small shop well: