Welcome to the Guild, here's the secret handshake.
I like the general style. I might steal the glow outline for my current map, I've been thinking about spicing it up somehow.
Any case, there's a thing called the River Constabulary here: their duty is to point out when rivers don't make sense. It's a simple thing to notice and fix, so don't mind when it happens.
Like about now: your rivers are strange. A good rule of thumb is that river always flow towards a point, they gather and join together: you have a river that goes from one coast to another and then again to a third coast, through a mountain range in the middle. Good news is it's simple to fix that kind of kind by simply cutting the rivers in the middle so that you have three rivers now that all run to one coast.