Initially I had an idea for a world that was an offshoot of high fantasy, but honestly the more I thought about it the more it felt redundant with the amount of material in that genre already. I have been fiddling with THIS WEBSITE that generates random indie ttrpg settings as an alternative idea generator to get some inspiration. Current best option (out of two rolled so far) sounds like a sort of far-future post-apocalyptic solarpunk archaeological...thing. I'm still working out how exactly to weave some of the incredibly disparate options I rolled together, lol.
I will roll one more and see which one gets my juices flowing the most, then see what I can hack together.