ah, i didnt think of that, its a common thing though, scanners always seem to fuck with pencil sketches.
bit knackered n not hanging around long tonight so ill leave the critiques for the future, i got you on my watch now though so ill go through next time.
i will make a suggestion though,
more so for your portrait sketching,
if your up for it, or if you just want to see some awesome realist sketching, tak a look at cataclysm X's gallery.
she is an absolute prodigy at sketching, its scary the likeness shecan achieve when she really puts herself to it,
ill pop a link down the bottom.
anyway, she also has some tutorials and WIP shots of some of her work, your probably beyond most of it and pretty set in your own styles but i reckon it might help you with identifying areas that you might have otherwise overlooked, goes right into te behaviour of certain areas, like facial hair for instance, not just just how todraw it but the properties that make it act that way, very handy when it comes to drawing it, just thought you might be interested.
but check it out anyway, even just as a fellow artist appreciating work.

cataclysm X
[link]

no worries, helps me too, im horrible at lineart so always looking for other peoples. ill try get my other stuff finished off soon so i can get started on this one.

your welcome, look foreward to more submissions

thank you, going to sart using more of my own sketches soon