It's actually quite simple. The more complex your game is, the fewer people there will be who can actually understand it. That's not always a bad thing mind you, as the people who do take interest will often be more appreciative and stick with the RP longer. You will need to really sit down and think about how the game will be run though. If you have a system where battles take twenty turns to resolve, and each player posts once a week regularly, the average fight will last ten weeks, or two and a half months. You will also have people taking momentary or permanent leaves for various things, and they might not always tell you about it. You will need a way to resolve these battles. There will also likely be a shift from storytelling to winning, though I've been told that's the norm for NRPs anyway. 

If you have interested players already, pitch this idea with them and see what they have to say. If you haven't made your interest check yet, maybe try making this game and testing it yourself. Maybe you can even lasso a guinea pig into trying it with you in PMs before releasing it to the public. The question isn't should you or shouldn't you, but can you, and that's not something anyone in here is going to know.