To the dev, please don't take this the wrong way but take this as what it simply is, advice.
-The first two separate parts could be combined and expanded into a prologue with what ever your planning for part 3
-If it takes three months to put together enough content, the so be it. Updates with content are more likely to attract interest.
-Don't push adverts for your other games. If your main game is good then people will look at your other games.
-I would also suggest a bit more background and character building between the main protagonists.
That's all I have.