The cross on the tabard looks fantastic. The folds on the cloth are just perfect.
Did you download some kind of custom brush for the chainmail, or make one yourself using a stock photo? I didn't notice it until I zoomed in, but the pattern is noticeable, like it was put in there with paint bucket. I'm not complaining though. Zoomed out, with the lighting on it, I can't tell and it looks very natural. I quite like it.
And now for the complaints:
- The helmet is, frankly, really sloppy. The lines are really wobbly and the perspective is inconsistent. I think you need to be more patient when drawing your lines. Maybe spend a little more time sketching and doing construction.
- His head and neck don't line up with where his spine should be, relative to the torso. I wish it were moved over to the left just a bit. Again, looks like a problem that should have been fixed when you were sketching.
- The chainmail is too form-fitting around his arm.
Here's a good video of LindyBeige wearing tailored chainmail. Notice that it is not tight, but it fits. The curves of his arm shouldn't be suggested at all unless his arm is lifted and he isn't wearing any padding underneath (he should be).
- Shouldn't his coif be tucked into his tabard? Man, now I want a tank top with a Hospitaller cross on it though.