To Max: Yes, you are very right. I'm probably going to make some major rivers

To Leen: I don't like that archipelago either, I'm still tweaking it but the core of it is there: a large group of islands connecting the two continents. For the lakes: what would you suggest doing for these? Making them normal lakes? Is it believeble that they are so large? For the big one on the top-right continent, I was looking for something like the Dead Sea, defined as an endorheic basin (a lake with no outflows). For the other big-great lake, I'm still not sure.

Thanks for your answers