I watched all three videos a couple of times and did not post up immediately. The reason was I needed to reflect on what I saw. First off, I want to compliment you on making great progress with such a young pup. You obviously have succeeded in teaching him quite a bit and he is definitely a keeper!
The distractions by the other dog were amazingly ignored and the pup using the hide hints that your primary purpose for this pup may be to hunt (just a guess). I use a hide often in training, but I never release my dogs directly from the hide. The reasoning is to avoid making an expectation out of the hide becoming a launching pad. They come to heel before making any retrieves.
It is very good to have a precocious pup for your first. You've succeeded in getting him to focus and be responsive. That's a huge advantage down the road. His delivery at that age is outstanding and consistent. He obviously is having a great deal of fun and that is because of your approach. Good for you!
I really only have a couple of things that jumped out at me. First of all, he was sent on his name for the first mark and on "back" for the second. Then again, I need to balance that with the fact that he is only is only 6 months old. I would be sending him on all marks with his name for the release and pile/blind retrieves use "back". Make the difference a clear distinction.
One last thing, the release to go could be a bit slower and calmer...don't rush it. The "hand down" cue is best issued slowly with no distracting motions. I believe you are trying to convey enthusiasm to the pup, but I like to release my dogs quietly from the line (most of the time) to avoid feeding anxiety.
Thanks for the videos....they are very cool (and not because of the snow).