Its been a while since I posted but here are my thoughts.
As mentioned earlier, there are other manga authors that are still continuing their works like Kentaro Miura, Yoshihiro Togashi, George Morikawa, and others who are famously known for their slow pacing or long hiatus periods. Guyver is no different, it has small periods where all the chapters that we have were done in a small period of time with long idle unproductive time in between. Since Guyver is Takaya's only major work, I believe he's just dragging the series out for reasons that he only knows (could be that that series is his life support for his career/reputation, or other more personal reasons). IMO I think that Takaya will finish the story in 20 years (give or take), and it would be very unlikely that anything would happen to him within that time that would prohibit him from doing so, and as others had previously stated, the series has developed so much, that Takaya will have good control over how he'll end it. With a lot of thought put into its development, Guyver will most likely end well considering the fact that Takaya has had so much time in working on it, plus its his magnum opus, Guyver is literally his life! (This is assuming however Guyver remains supported throughout that time and doesn't get dropped)
I honestly love guyver and I've rechecked all of the previous chapters and I feel that the ending will involve some sort of Armageddon, in the since that the creators will arrive and in my opinion either them or their "enemy" will be the main villians and chronos/or guyver one's team will probably be humanities only resistance against them. From seeing how events have turned out, and previous hints, I feel that the story might head that direction (I could be wrong though). It would be interesting though if there was a thread started about important things that have to be answered before the series ends.