I don't know how you came to that conclusion but I'm not angry, I just wanted to give my point of view on the development time, just to clarify.
Hopefully I can hire someone to increase development time, but I imagine it must be very difficult to trust the quality of your work to someone else.
The thing about these kinds of games only having one developer is that having two of them often compromises the project in ways you often couldn't even imagine before starting out. I
would give examples of games that failed because a solo dev teamed up with someone else, but I can't think of any
good examples of that. At least not of games that are on this site (and mentioning games
not on this site is a no-no according to the rules...)
But you are right: Trusting someone else to maintain not just
the quality you seek for your game but also
the artistic vision behind it is incredibly risky, and most often not worth the bother when it comes to visual novel games. Sure, it might be
easier at times, when one person does the rendering and the other does the writing/programming... But it's still a right gamble!
-Mal