I like the softness of the portrait you are working on as opposed to the linear style of portrait you got of the DOD. Yours is coming along really nicely. There may be a few spots here or there where you might be able to use a liner to crisp up some edges here and there, but that's all I might suggest. The DOD one has a lot of outlining in it (which makes it look a lot more cartooney - which isn't a bad thing, but if it's not what you're going for, I wouldn't outline everything like that).