Goblin is a low population server for sure, but it's not dying. There are pros and cons to all population sizes. A pro, for example, to our smaller population is that hunts aren't as much of a massive Zerg fest as higher population servers, we can actually experience the mechanics of A ranks and find a challenge in defeating them. On higher population servers you might not even lay eyes on them before they're dead.
There are cons too, like fewer PF groups, but that is normal for a server our size. Our server isn't dying, nothing needs to be fixed, it's just a different dynamic than the larger servers.