Also the toolpaths generated had some really wasteful moves where it was carrying out a ridiculous amount of small plunges to nibble a bit then move. i think the time could have been halved without these small plunges.
That is sometimes a sign that the area you are trying to machine is the sames size/too small for the specified end mill.
An alternate way to approach this design is to use a VCarve strategy with a flat depth using the V bit and the 1/2" end mill.
See the attached file for an example.