Makeup is actually quite nice to draw in. The grease sticks (also known as lipsticks and concealers) are a bit like soft oil pastels, and eyeliners are splendidly soft pencils. Mascara can be a bit tricky in use, but it can contribute nicely to an effective hair illusion. Eyeshadow - which, in my makeup bag, is usually pressed powder - can be very awkward. I have got some tiny balls of pressed-powder eyeshadow and these are quite good because you can control where to squash them (but they do tend to roll off the paper).
I have found that blending with a finger is very nearly essential. Eyeshadow and other powdered cosmetics will stick to the grease underpainting if pressed in, so allowing their wider range of colours to be made use of.
As to subject - well, quite apart from this being my default trying-out-a-new medium subject, the colours are perfect for portraits (and for figure studies). I want to find the bag of really old makeup that I know I've got somewhere, not least beause I am pretty certain that it has a less "natural" range of colours. Then I might think about a different subject.
I wonder where that bag is.