I've been thinking for a long time now, that it would be a good idea to make a continuation of fate/stay night, specifically speaking the UBW route. so, this is what it's like in my mind:
it's about a year after the fifth Holy Grail war. All side had reached the conclusion that the Grail had been destroyed by saber's Excalibur, Shirou and Rin has been studying abroad in London after that occurence up till now, leaving the Fuyuki in charge of Matou Sakura as temporary guardian. one day, the command spell suddenly appeared to 7 mages across the world. The seven were then either departed for or already been in Fuyuki from their respected countries, either left with their servant or yet to be summon their own. This is I had in mind: the main character was from France, an acquaintance of Rin and Shirou that they meet on one of the mission (will be explained later), an outcasted italian mage that work as a thief for magical items, the representative of almost-crumbling Einsbern, mage from association, the freelancer genius alchemist from Russia, a priestess from church, and a girl of small magus family in Japan. The servants accordingly will be saber, berserker, caster, assassin(later avenger), rider, lancer, and assassin. Note that the Grail's time axis is disrupted by saber on fifth Grail war, resulting in it's out-of-cycle appearance and strange influence on several servants
This is a story line for my doujin manga, so the details won't be as good as project that intended to be novel, feel free give me your critics or idea or question regarding that matter, and please forgive my grammatical error, since english is not my mother tongue. Continuation of this project would be written if there's enough demand, feedback, and spare time. Good day.