If few visitors return, if you’re always having to prod and push people behind the scenes to participate, and if activity doesn’t seem to be picking up…you have a concept problem.
You don’t solve concept problems by changing platform.
You solve concept problems by profoundly rethinking who the community is for and what the community is about. This usually means finding an edge and going to extremes with it.
Within your topic, what do a small group of people care about really passionately? What is the one thing that gets them emotionally hooked? Then begin to build the community around the edge.
Backpacking Light is a terrific edge. If you want travel communities, go elsewhere. If you want the lightest possible backpack, go there.
The temptation is always to create a community that appeals to the maximum possible number of people. Don’t do that. Find the small niche that you can dominate. Believe me, the big fans will tell others and you start to grow. It’s a lot easier to find success when you narrow your vision down to a core focus.