Ok, so the list of people who have shown interest:
Antioch, Shihong, I'm going to say that DemonWing is the last one in, as I'm hesitant about running for too many people (and my friend never finished her application for the site so her spot is vacant, then taken by him).
If something comes up, or I decide I can allow another couple players, I will post here saying so.
As for starters, I'm going to say "yes, any mon, within reason." Ideally, I think I'd like you to pick a usual starter (any gen/region), or the lowest form of a three form evolution family with a type appropriate to your city's gym. However, that's not a huge limitation, as there are plenty of three form families, and there are many more cities and gyms than shown in the anime or games or manga.
Being the kid of a gym leader is ok, but I'd like characters to be no younger than 16, so as to stave off the squickiness of anything younger being in an adult roleplay.
Understand that in my interpretation, the Pokemon League is essentially the governing body of the pokeverse, with the Elite Four being the highest level of government for their region, and the Champion being the actual head. When a new person defeats the champion, they have the option of taking his place in the government, or allowing him to continue being the champion. Most kids, when they defeat Lance or whoever, are sat down by the Elite Four, and probably whoever gave them their pokemon, and have this explained to them, and end up deciding to let the adults continue running things.
In this model, gym leaders are typically the heads of towns unless, for some reason, there's someone who commands more respect who hasn't told the town to follow the gym leader.
I'm thinking that under this model some kind of trial by fire may exist in lieu of a standard court of law. Criminals may be able to elect to have a battle with a court owned pokemon, typically something final form and high level, with the size of their own party determined by the severity of their crime (up to "no party, you fight this on your own" for the most severe). But I'm not sure about this. I'm still thinking on it.
DemonWing, this is going to be a bit darker than the games, possibly more in line with the manga (which I haven't read, but have heard is rather dark), or possibly darker than that (again, haven't read, so I can't give more than that). But, like I said, poke-zombies is a possible plot point, and I am a horror nut, to a certain extent.
NotCarrot, a professor's kid would be fine, especially for a professor more akin to Fennel than Oak and co. On the other hand, be aware that I'm vaguely considering using an idea I had that the professors are all part of a secret cult that forces them to change their names to that of a plant.... I don't know if I'll use it, and I don't really know how nefarious I'd make the cult, probably not very, seeing as how I truly respect the pursuit of knowledge.