I see that a lot of people make rather elaborate roleplay requests with their scenarios and worlds planned out rather extensively
A lot of it depends on the person, too. Personally, I like to see a lot of details or well thought out plans before I commit to a game. Pictures, specific plots, specific scenes, etc. In the past, I've joined games that were just too broad or basic, and I was struggling in them. When I would approach my partner, I would get replies along the lines of 'whatever is fine', and that would give me no motivation.
Don't get me wrong, a lot of people can do fine with just that. Sometimes, I'll post a basic idea, then tailor it to the preferences of my partner and myself, and get something a little more specific.
Bottom line: there's nothing wrong with starting and/or staying simple.