looking nice so far! some good shapes. i personally don't like that island group in the middle, it seems to be too regular, too well ditributed...

About the lakes (i don't much either):
If a lake has no inflow, it will vanish with time, in your case with very much time if thats ok with you, then its ok to have such a lake. you probably need a explanation though, how the water got there...
I think i read in the river tut here in the forum (but i'm not sure) that a lake only has one outflow. it can have more, but they will merge in one.
Correct me if i'm wrong, riverpolice

Cheers