No, you can use any of the preset tilesets, (I'm thinking Celadon Cities) and then afterwards, I'll go in and find out what I want to change on the Tileset or add to it. (Like a Tyranitar Statue I have been working on).
Oh, and I sent the rom to you!
I have nothing done yet. /: I wanted to get a team together and discuss everything first...
I'm going to send you the rom we're going to use. and you can just start mapping a very big hometown. Remember, you're going to have 2 rivals, and make a good space for viewing the first battle you witness on your way to school, and then try and make it as city like as possible