I am now going through the 'painting by model type' phase. It is actually quite interesting and you get to learn a lot about the model when you paint the same one several times. Always searching for ways to make the models seem different. Colour is the obvious way to do this but also the position of gore and blood trails can help. The aim is to draw the eye to different places.
There is quite a lot of detail when you look closely at the model. I like the face and then there are things that don't stand out straight away, the mouth guard, the stethoscope, the bow at the back of the neck even a small name badge over the left boob. All these disappear when the undercoat goes on on and then present themselves when the model is subjected to some close scrutiny.
Again I have gone for different uniform colours to separate the models.