Oh, one other thing, on the second and third map there is a fork of the river that runs right over a mountain. It is the first left hand fork on the central river.

It's just a minor issue, but still a little distracting.

Also, I agree with the river issues on the first map. The two forks that are going towards the sea don't look natural. If they were flowing from highlands or something like that, then it would be more natural looking.