It depends on what you understand as "mediocre". To me, something mediocre is something unoriginal, common, with no personality. A comic about a mari sue superhero saving the day, or a fanfic full of romances will always be mediocre to me, no matter how good the drawing is. So, it is actually easy to scape mediocrity, but also risky.
Care first about having an identity, a personality in your stories. Be you. And then you care about improving your skills.
Your drawing style doesn't have to be the best, but it has to be your own. As an example, I draw in actual pieces of paper even though almost nobody does it, but that's me, that's what I like.
This is also valid for storytelling. There is some cliche you don't like? Get away from it. Do you like some controversial topic which most authors try to avoid? Be brave and make it the focus of your story.
If you want another example, years ago I wrote a story which took place in a very popular universe. It looked like a shitty fanfic, but then, the popular series in which it was set bacame just a nice background to tell the adventures of an alcoholic communist metalhead.
Be creative, and do everything you want, even if it looks like a bad idea. Think first about a crazy approach to tell whatever you want to tell, and then make it look interesting and attractive. That is the beautiful part of independent publishing: The fact that you can share any original story that no publisher would ever publish.