Seeing Shinpachi all grown up after the time skip and in the same restaurant as chapter 1, makes me feel a bit sad, Gintama has ended.
Knowing Sorachi, the Yorozuya hasn't ended, it'll come back together in the next or last chapter. Gintoki probably went to pay his wishes to the Utsuro/Soya. Kagura went to do the same for her family.
Also I think that Shinsuke was in the Tendoshuu room, to try to save the art and the inhabitants. He probably must have spread their temporary immortality to Eart and saved the humans, or something.
Now, where are the Shinsengumi and Gori-san?