If the Siege Battle system they are talking about implementing turns out really well I think 2Moons has some future...without it not much at all. The grind is absolutely ridiculous so to keep people playing there has to be a justification for all the time they are investing.
If the siege Battle system works well and it's fun then people will invest the time to become as effective as possible for the sieges...if not then most people won't feel like grinding it out is worth it. In lineage 2 people were on the grind for 1.5 years because the siege system was awesome and it bread an incredible system of alliances and political agreements on every server.
Bottom line without some real content 2Moons won't be anything to speak of. It will always have some subs cause it's free but the typical free MMORPG model won't drive this lil fella home. Archlord is a pretty good example of what not to do and the 2Moons grind is at least double the Archlord grind.