Hello! I'm also new here.. I'm no expert, but I'll see if I can help! You have a very nice sense of proportion and anatomy, but your linework looks hesitant, like you keep going back over lines to make sure they're in the right spot. I bet you could improve your work greatly by placing down some nice dark bold lines and leaving them alone. I find that working in pen helps with this, since it kinda forces you to be bold. Just my opinion though. Good luck, happy drawing! :)
Go for it! Pen's a little scary at first but once you get used to diving right in and letting the lines do what they want it's a really pleasurable experience. Plus it makes working in less-permanent medias a whole lot easier. It's a great confidence-builder. Best of luck!