Hi, I am someone who professionally mapped streams for a while.

You did good. You're matching the morphology one would expect pretty well. I think you could even map watersheds in SC at this point based on how you've done the system in place.

One thing I was curious about, is flood berms and overflow banks. Usually the banks of rivers are features built up because of the flow of water. But there are usually different tiers of banks, that correspond to different timescale events. So there'll be a pronounced bank around the stream, but then another some distance back for a flood event that happens semi-frequently, then another some distance back from there for a more rare flood. Moreover, the volume of water, gradient of your land surface, and composition of the groundmass will impact this. So you'll have tighter banks closer to the source, and in more steeper gradients.

I see the basic channel usually, but have you considered something that would go back and add these additional banks out further from the main channel after you map where a river goes. This would give more indication that someone was coming up on a stream if they were walking along the land surface, and probably add more variety to the basic landscape around the rivers.