Like [@NuttsnBolts] said, I think it has more to do with how the interest check is presented. You've clearly done all the advertising you can do, you just need to make the product look better.

A snazzy banner is one way to draw them in, and you've written about your world in great detail. While roleplayers like playing in fleshed out worlds, they don't always like reading through wall of text after wall of text. So you need to trick them into thinking there's less text than there actually is. There are many ways to do this, but my two favorite methods are...

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Pictures! At just a glance someone can get a feel for the mood of your rp with the right pictures. How many you use is up to you, but I admit that a picture usually makes me stop and read what an RP is actually about. Another thing I like is...

[h3]Multiple headers[/h3]

People may decide that a wall of text is too big to be worth reading. By breaking up a wall of text into smaller segments, it looks less intimidating. 

[h3]However...[/h3]

The real decider is "what's on the market" and what the RP gods feel like. There are tons of sword and spell fans, but the forum is saturated with these types of rollplays. As a result, only the very best can garner more than a smattering of players. My Danganronpa RP had 13 players in the first few days of putting up the OOC because there hasn't been a danganronpa rp for 6 months, and the new game was going to release in Japan in just a few weeks. This created a very ripe opportunity for me!

[h3]My Advice?[/h3]

I agree with NuttsnBolts, you should try and roll with what you have. Something else to consider is that one of your players may get busy with real life responsibilities or just drop out entirely. You should have a back up plan if or when that happens, otherwise the RP could grind to a halt on account of a simple oversight.