As an avid fanfic reader, I say write it anyway. I've read sooo many stories with similar plots and characters, and enjoyed each and every one. Like you said, the base might be similar, but the execution is different for each, and that's what makes them entertaining.

Yes, there might be a few people who might say you "copied" someone else's idea, but in reality, no idea is ever one hundred percent original. Think beautiful, tall elves. That has been reused over and over again at least since Tolkien (and probably before too).

At least in Ao3, most authors actively encourage people to either use their work for their own inspiration or write works similar to theirs, because what they are writing is what they themselves would like to read.