I haven’t touched Blender in like a year so this is what I could spew out in like 45 minutes. Still getting used to Blender 2.8’s interface though.
Any Blender tips would be very helpful, also any suggestions, such as me considering going back to making GFX and maybe selling? Idk.
Thx
Not much to really judge if you should sell or not, but from this, I would say you should keep practicing! Not that it looks bad, but practice makes perfect!
Looks good dude, just keep working on it and one day, you’ll be happy about the project you created, do not worry, I get that feeling too. 
With a little more practice with lighting and poses, you could be really good! Just keep up the practice!
