Oh yes, I know you all fucking adore this question.
But seriously, new world when? I honestly don't see many people at all against this. Everybody knows that currently, end game is shit. The rush of a new world brings people back, and for good reason. A new world is untouched, it's dangerous (hilariously enough, more dangerous than end game despite everybody being bored and going out looking for people to mow down to kill their boredom), there's a lot of fun to be had with the early to mid game.
I know that at first glance, it may feel more logical to wait out on creating a new world until you have created a sufficient plan for end game, but you would be wrong in making that assumption. There's no sign of any clear end game plan yet, from what I'm seeing anyway, and thus it's still no doubt going to take a large amount of time before one is even remotely ready. By that time, the already low amount of people playing now will just keep diminishing. Or it'll remain stagnant, assuming that the people we have left now are the usual crowd who never abandons the game.
Why not get this new combat system you guys are working on into an acceptable state and then do one of two things, comfortable in the fact that you can refine it during the new world.
1. Roll the combat change out with a brand new world. The combat change alone would be an exciting enough new edition to get people interested, numbers would jump up again and everybody would be happy. (Preferred option since it accelerates us into a new world faster).
2. Throw the combat update on live, give people a month to mess around with it (just to see if there's any major fuck ups), and then give us the new world shortly after.
The benefit option 1 also has is that the new and returning players will be on a more even playing field with everybody else as far as combat goes, rather than having to deal with people who have already familiarized themselves with the system due to having the time to play with it that option 2 would provide.
Honestly, if you were to do a poll, right now, asking if people wanted a new world soon, I have no doubt in my mind that the VAST majority of players would vote yes.
Let me just make one thing clear too. The small amount of people that are on daily now are your most loyal players. These are not the type of people that are gonna drop the game because you made another world. The people that would have done that are long gone because end game on here sucks dick. No offense :^)
Your action plan for that new world could be something along the lines of this too.
Finish finessing the new combat formula for a few updates
Work on end game
Tada. Everybody is happy.