I wouldn't sweat too much on the Vmcg/Vmca consideration. Just be aware of it as part of your pretakeoff planning and general decision processes.
One needs to be low weight and using a minimum speed schedule to be exposed. That is, the weight range where you see the V speeds run constant with reducing weight.
However, be very wary, also, of crosswind operation at low weight. The declared V speeds will be based on nil wind (7kt for older UK certifications). In the real world, the V speeds will increase with crosswind from the failed side. Think of increases in the order of 0.5kt/kt for twins and in excess of 1.0kt/kt for quads ... if you have a high crosswind limit and you are at low weight with a min speed schedule .. the potential is there for a BIG surprise.
One area which you can control is that of empty ferries .. if the runway isn't short, why go off at the minimum speed schedule ? Maybe use a higher speed schedule appropriate to a higher weight ?