And now...the novelty is wearing off.
A small handful can't keep a place thriving.
Well, I guess that depends on how you define success for something like this. If the extent of moderation is minimal and there is low but steady-quality traffic, why not let it run and see what happens? You may see slow but steady growth in the long term.
Alternately, if you really want to boost traffic, make this place an 'official' home for your vids (yeah, yeah they're on YouTube, but you know what I mean). Use the blog section and have one thread per vid where the first post is your vid and the rest is the peanut gallery piping in.
You got pretty good name recognition for your vids (heck, you even have a microbadge). In fact, once you set things up the way you want here, spam every BGG user who has your microbadge about this forum and that it's now housing your vids. You just might be surprised.