Running an online game's a commitment. Considering the amount of time and effort for the player a player must invest in playing your game, I believe it's important that you secure a long term solution to keeping your server alive not just for financial success but also for the sake of the people who do play your game. After all, I imagine people would be hesitant to try out a game they know will have trouble staying around for the next year or two.
A suggestion might be to decentralize server hosting? Like, design the server and player clients in a way that eventually you can sell/give them both away so anyone with the things can open up their own server. I don't think I've heard of any MMO's that have done this, but I believe at least that older RPGs like Ragnarok Online and Lineage had thriving player communities for so long is because these games have managed to throve beyond official servers, albeit in the legal gray area. Or go the Diablo route where online multiplayer only supports smaller groups.
Your stuff is amazing! I really hope it sees the light of day eventually.