What is it thats subpar? The modeling itself or the character design?
I would focus on character design first and then learn proper topology for building it. There are tons of books out there about 3d modeling that will give you a great head start. Youtube frightens me a bit because you can’t be sure what you’re watching is proper or not.
Look at some of the work on CGS, pick out your favorites and contact the artist. Pick their brain. Many will be happy to answer questions about their work. The more artists you contact the better it will be for you.
Your resources for learning are important so be sure to take a little bit of time to make sure they are good for you.