MS as been gone a long time, you need to do something to bring it back, dit has obviously lost you subscribers, and still causing you to loose them, it makes sense to me, to do an update to MS asap. It's up to you, but if your wanting to get new subs and not loose more I would make what they are subbing for in the first place.
BlueCat who created Ecchi Sensei left a really bad taste in people's mouths when after making 3 weeks in his game, and under very different circumstances suddenly wanted to make changes, and wanted to combine everything together. To date after 18 or so months and a broken update which was done to prevent his work from being abandoned on here.
With no end in sight of him ever continuing it, with broken promises etc.
You have done a lot of work on MS just as much him if not even more, people haven't forgotten BC and unfortunately for you, people are seeing you in the same light has him. Sure you might be making another game, but it's not the game subscribers subscribed to you for and it's obviously the reason they voted with their wallets and stopped subbing you.
It might seem like a great idea to have a vote, but in hindsight it's done a lot of damage to your subscriber numbers, and continuing to loose them obviously needs arresting, and gaining new subscribers or some of your old subscribers back. There is literally only one thing you can do and should have been doing from the start.
I am sure it must have been very conflicting that you are trying to flesh out this universe your creating and your trying to lay some kind of foundation, but it's pretty obvious the thing you should have been doing until it was complete or passed onto another sequel.
While it might seem tempting to just do those 2 remaining updates, personally I would refrain from doing them, and concentrate on the more important thing to you right now, which benefits you and your subscribers, and that is to get a MS update out next.
It's been gone a long time, you need to get the game back out there, so people know your really still developing MS.
Imagine what your original subscribers must have thought when you back tracked and decided to make a new game, with no new updates in sight for the game they where subbing you for, helping you financially to make the game, all they got was something they didn't want, which was you not continuing to update MS.
You need to put DiT either on the back burner and create a new MS update which can only help you in the long run with your subscribers (will help greatly in keeping your current subscribers) and gets MS back out there, with the promise of more updates, or you can do what some solo developers have done and continue to do, which is develop both together. Or you could develop both together, so you can get both updates out there for both games, that then leaves you with just one more DiT update, which you do alongside MS again, then you go to MS and work on that until it's complete or moves into / onto a sequel. You will get more subscribers this way. I would also suggest you move over to sub star where there is no censorship and draconian rules. Westy is doing magnificently on sub star uncensored and so you can you, but it has to be MS build up trust again and then you should be able to keep same subscribers as you go forward and gain more along the way. Thus your problems go away at least financially as you posted.