Critique on DrawRight type drawings

Hi r/artcrit, first time poster and art beginner. I'd love some feedback on these two drawings. I have gone through the Betty Edwards' book and am following that technique roughly.

• I've scanned the drawings and overlayed them in PS, so I can see where I messed up on proportions. How else can improve?

• Going forward, what other methods / books / techniques should I take a look at to improve? (My goal is to one day paint portraits as well as draw, if that's relevant)

Thank you!

#1: http://imgur.com/a/HRDnA Took me about 2 hours. I feel like I'm at 90% of my ability here and if I put some more time I could improve it a bit but not much. I messed up the white part of the beard, wasn't sure how to fix it. Reference: http://i.huffpost.com/gen/1317976/images/o-SADDAM-HUSSEIN-facebook.jpg

#2: http://imgur.com/a/X4taU Took me about 1 hour, I feel like I'm at 70% of my ability here. Got a little lazy and frustrated when the drawing wasn't turning out recognizable to the reference. Reference: http://more-sky.com/data/out/12/IMG_554705.jpg