Awesome! Thanks for making that summary! Here are a few additional suggestions that are within the original $50 parameters.
I feel like I mention this knife in about 75% of my posts, but the Boker Plus Exskelibur I is an absolute steal for $50. You can also find an Endura 4 for $50 if you look around a bit. (I see the Native and Delica made the original list, but not the Endura.)
My collection is mostly folders, but I have a few fixed blades that were under $50 and very well-made: