arm studies look good
for the image of the bones being lifted, all the little tendrils and shapes appear very similar, this can be a way of creating dullness in an image, it's a very common thing to get into
it's one of those kind of filling space when you're unsure habits
and it applies to spacing as well try to cultivate an eye for pleasing composition of space balance and having some hierarchy of detail size
it will help your images have more warranting of a prolonged glance and some eye travel
if everything looks about the same size spacing and detail it can make your eyes go, well I've seen one area, its all similar so I'm done
just something to keep n mind, but a great way to apply your anatomy study while also producing something significant
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the nude is looking very good, particularly in the body where there is a nice soft touch to some of the transitions.
another common thing i see in many peoples work is painting along the edge of individual shapes and creating this rimmed gradient kind of blend for all areas of the image. It can create that very 'digital painting' look
just did a subtle paint over to show some difference you can get with a bit of painting with the contour of the forms in mind
It may help describe forms even better, look a bit more natural and let you get some more interesting looking blends
anyway, hope that helps