Loosely Inspired vs Original Content?

Hello! For the longest time I've been trying to create a world inspired by the Etrian Odyssey series, which is essentially this difficult dungeon crawler that involves a group of people trying to get to the highest floor. With the world building I've done I tweaked a number of things, but admittedly a part of me is unsure of incorporating the "dungeon" as a whole or actually moving away from the series for potential publishing purposes.

How do you guys feel about loosely inspired or almost fanfic-like worlds?

I think it's a no-go if you're aiming to be published, but then again, there are tons of similar series out there.

I don't mind the loosely inspired stories as long as it isn't blatant. The Eragon series has a simialr plot line to Star Wars, but I didn't mind because there was enough side plot that was different. (Heck, I didn't even notice until someone pointed it out to me.)
Also, if it's in a different genre, that might help.
P.S. Maybe use a different type of prison, idk.