Hey JM, to see where your bar is, I think it helps to get some distance from your own writing. For instance, if you reread some of your older stories, do you generally like them or not?
If you cringe when rereading them, then you might have a bar that's too low. But if you think that your old pieces are fine, then your bar is most likely on the higher end.
Another indicator is how long it takes you to finish a piece. If it generally takes you less than an hour to finish an article, then you're probably on the lower end. If, however, it takes you days or weeks to finish a simple article, then your bar is probably higher than it needs to be.
Either way, as long as you're improving, as long as you're getting more positive than negative feedback from readers, and as long as you're not getting so frustrated that you're about to give up, it probably doesn't matter to much where exactly your bar is. It's subjective anyway :-)