It is nice to meet you, Dr Tenenbaum. My name is Armin Arlert. I've been here a while now, so I'll try and answer your questions to the best of my ability.

Unfortunately, there isn't a way back. At least, not one we control. When people leave this world it is exactly the same way they came here - completely at random and without prior warning. Your stay here could be just a few short weeks or even years-long, there is no way to tell. But if it is any comfort, time in your world has essentially ceased to move. If you go back to your own world, you'll return to the exact same moment you left it. So your project should be all right.

As for pokemon breeders -- honestly, that depends on the breeder in question. When someone new arrives here, they are made either a trainer or a breeder, but it doesn't really affect what they can do. You can switch between them too if you wish. In general, breeders are people who put their focus more on producing pokemon eggs rather than gaining gym badges, though people have very varied motives. Some people breed pokemon as a job and sell on the eggs. Others breed pokemon more as a hobby. Some people focus on breeding specific types of pokemon or breeding them for specific purposes. I guess you could say I am the latter. I breed one particular pokemon to help repopulate wild populations, but really, the choice of what to do is entirely up to you.