Still not getting the curves right

If you want the geometry to describe the dimensions of a part which you are cutting out you will need to use an Outside contour.

To help in the dimensional accuracy it will further help to offset by endmill diameter plus 10% or so and cut as a pocket down to tab height or the penultimate pass. Where possible avoid slotting and add geometry and cut as a pocket

and/or

and consider leaving a roughing clearance and taking a finishing pass.