Clans are great, and I am into them and are a huge fan as I want the maximized realistic experience. But a clan leader is someone that needs to have been around for a while, knows the in's and out's of not only the LCPD:FR/GTA IV world but also have great life experience and management skills. It's harder than you think and not all fun and games and as glamorous as you might think. But, prove me wrong please and if you do decide to best of luck. My piece of advice would be to stay at it and keep working at it even when you might feel there's no hope.
All that advice has come from personal experience in starting up a clan.