@Kidany:
Or maybe it is meant for him and it just isn't the time for the Behelit to be awakened. I mean Griffith had his for years, and it never fully awakened until a certain moment. Because as strong as Gutts is right now, there's no way he can take out Griffith. Later on Gutts will probably be tempted to use the Behelit and sacrifice his companions in order to gain enough power to challenge Griffith.
Although another way seems to be however Skull Knight has gotten as strong as he is now, and that seems to be the path Gutts is taking to gain strength to take out Griffith and the Godhand.
I really doubt guts would sacrifice his companions. He's become a father figure and guards them all with his life. This is a much different and more mature guts then the one earlier in the series.
As for his path to taking on Griffith I'm sure he'll gain some kind of power or technique from the elves. He is on the path of skull knight as you said and that too will hopefully be explained in the upcoming volumes though I doubt it…