You seem to have the same problem as a lot of other manga artists. All you know is manga. (Not to be a dick) You need to draw real people. I mean Google gesture drawing and human anatomy. Learn about line weight and color composition. learn how to paint landscapes. Also learn the digital art program your working in better because that ice could be looking a lot better. You've jumped right into all this complex art without learning the fundamentals. Instead of learning how to draw a style you should focus on the human form and build the style off of that. (Things to learn) Gesture drawing-Anatomy-Line weight-Color comp--- You obviously have talent but you need to cover the basics.
I commend you for trying to help but I like how things look right now, if I want to improve my style then all it takes is practice till I get it right to how I want it to look, knowing only manga is not a problem, it's a choice.
You're not a bad artist but you've clearly got your own way of doing things and I've got mine, and I've been improving mine for 12 years onward, considering it was 2002 when I first started, I'd say I'm doing well.
As for software unfortunately it's just a cheap one for the 3DS but it gets the job done, if I had the cash I'd be producing even more fleshed out art but until then this is what I have to work with.
You've got nice art by the way.
Have a nice day.
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