In my opinion, Warcraft is slowly decaying which is normal after all these years and the number of new games that have been out since (Blizzard games: Sc2, Diablo 3, HotS and Hearthstone; but also LoL and DotA 2), so the userbase is slowly moving away from Warcraft 3 and by so losing interest into staying active on the hive (in general). Those that have spent a lot of time here are more likely to stay (or to come back from time to time) cause of the bonds they made with other members of the community. At the rhythm it's going, the hive will still have some activity in 2 or 3 years.
On the question of how to make the Hive more active (in other terms, what to make to give people some interest in joining/staying on the hive) there's several things that can be done.
First, a thing everyone can do : Being active yourself, there's no point for someone to join/stay if he feels lonely on the forums. (i know i didn't do it myself)
And now for the stuff that an individual can't do :
Expand the Hive to new games/horizons :
It has already been tried/done with more or less success :
- Starcraft 2 for modding, which i think was supposed to supplant Wc3, but failed, mainly because Sc2 modding is far more complex than on Wc3, as well as the universe being less appealing for some. So in the end it is active, but could be better.
- Programming & Game Dev (and DotA 2 modding) which aren't very active more complex than Wc3 and requires actual programming skills/knowledge, so once again, not surprising for it not to be active as it is not for everyone.
- Gaming in general (Blizzard's games and LoL), but once again, those parts of the forums aren't that active, maybe due to the fact there's less reasons to post in those parts than on modding ones.
- Artistic side of the Hive (Artist's Discussion), which is quite weird as some parts (Modeling, Texturing and Terrains) are bound to Wc3 modding (even if they're not dedicated to Wc3 exclusively, most of the things there are related to it) and the rest isn't. Those specific parts aren't even used for anything else than Wc3 (maybe a bit of Sc2 from time to time) when they're supposed to be for any kind of Models, Textures, Terrains, etc... (they're in Artist's Discussion and not Warcraft 3 after all) and it could be nice to see Models/Textures/Terrains done for other games (be it Sc2 or even related to the Game Dev part). The other parts (2d art, writing and sound/music), aren't quite active either even if they're not directly related to Wc3 modding (in the use people make of them).
So, in conclusion, none of those tries really worked out, but i think there's some stuff they could really use to become more active/appealing :
- Contests/Tournaments/etc... : If we think about it, there's only contests for Warcraft 3 modding, a few mini-contest dedicated to Terraining, 2d Art, Writing, etc... have been done in the past, but i don't remember having ever seen a Sc2 contest when a mini-map one could be a good incentive for people to come on Hive for Sc2 modding. Gaming tournaments could work too, i'm thinking mainly about Hearthstone as it is a 1v1 game and it wouldn't be impossible to find 16 or 32 contestants for it. On the other side, i think it's harder for team games (as in LoL, HotS and DotA 2) as it would require to find a minimum amount of teams (maybe it's possible though for LoL with its important user base and the fact that Riot Games could provide a RP prize pool as an incentive). Gaming contests on Warcraft 3 could also work (i'm thinking about Melee and popular maps)
I've seen that you're experimenting with Prize Pools (outside of reputation points ofc) with the Cinematic Contest and i think that it can be a good idea, even if 150$ is a lot and can't be done for every contest (there won't always be people willing to give 50$ for it), but small prizes such as 10/20$ could work. That is in Hive's current situation, if the site gains in activity, then i think it would be possible to find partners to finance the prize pools (instead of a few users doing it).