start small, like any good game dev. dont scope too big or else you face not getting enough progress done or burning yourself out before it reaches a self-sustainable state.
lot of the best builds come about from having a general idea of what they wanna do, but just focusing on finishing that small part they are working on and make it look kickass. or something like "hm man this awesome house would go great on an awesome cliff" and just kinda roll from there.