Being inspired by somebody else's concept to create something of your own is great-- using their ideas instead of your own is not great (and by "you" I mean the generic "you").
See, pre hyphen and post hyphen here are in conflict. At what point does "being inspired" cross over into "using ideas"? What's wrong with using ideas as a jumping off point?
Ever heard the saying "good artists borrow, great artists steal"?
BTW, I'm curious, what type of stuff have you written?