Try drawing from direct observation, not photographs. It makes the work harder, but you'll see more depth in your portraits. If the work is about a loved one, try maybe drawing another member in your family or another person who holds similar traits to your grandmother. If you want to pursue drawing musicians go to a musical event, which occur all the time in the tricities, and draw them as they are setting up or playing. They might not be famous but they are producing great music all the same.

Other parts of your art will benefit from drawing from direct observation. Your compositional skills will increase because you will not be confined by the limits of a photo. You're color will also probably become more vibrant as well. I loved the landscape of the sky with the trees on the lower edge. It has nice, lively colors to it. Some of your other work gets dragged down because of the muddy colors.

Good luck on the comic. Try getting models to pose for the characters, so you can make sure the anatomy is right. You've got a great start with your artistic life, continue pursuing it.