Hi Ynitial,
Having more control over tab placement is another item that's been on the ever-growing todo list for a while. We're looking at simply adding an offset parameter that allows the user to move where the tabs begin within the distance between two neighboring tabs. This has definitely been something that I'd personally like to see added ASAP as I am always using the profile milling operation and including tabs for cutouts.
The next best thing to manual tab placement would be to use the paths-carving operation. You can use the Trace To Paths function to generate a path with an offset equal to half the diameter of your cutter's flutes. Then manually edit the resulting path to have a gap where you want a tab. Let a profile milling operation do material removal down to where there's enough material left for your desired tab height, and then use the paths carving operation along with the paths-layer from tracing the shape as input to do the final cutout. Just remember that the paths carving operation doesn't allow for any kind of tool offset, being that paths are not considered to have an inside or outside to offset toward or away from the way that 2D milling operations do with their contour input.
Hope that helps! Let me know how it goes, or if you have any other questions or need help with anything else :]
- Charlie