In the words of Will Smith (Man-God): "Heeeeeeell no". There's still so much left to happen and resolve. The only way I can see it ending at this point is if Togashi has decided he doesn't want to draw anymore, and I can't see that being the case right now. Gon meeting Ging was never really the point of the manga. It's more about the journey (that sounds like a cliché, I know, but it's true). And if Gon meets Gin now? Well, he can just go on another journey. Or Gon will say something like "This doesn't count!!" and get Gin to run off again. It doesn't really matter. It's not like now that he's met his dad Gon is going to go back home to Aunt Mito and live out his days peacefully.