I've always wanted to be a Gym Leader, but now that's too cliche. Sure you get to be famous and apart of the top eight leaders of a region, but you'll never get to go anywhere, and when it comes to Pokemon, it's all about the travels.
So, that in mind, I'd probably just stick with being an average trainer, competing in gyms and journeying to all the Pokemon Leagues in all the regions. Of course, I'd love to have some friends along, but the idea itself makes me content. ^^