I think you mean you like the lore. The story itself is your usual mediocre "get gym badges and stop generic evil team from doing something bad" and suffers from pacing issues, shocking swerves, and just not being thought out well. The lore on the other hand is easily the best part of the game. An ancient war? Pokemon actually die in it? It had kings in it, including one so outraged by the death of his Pokemon he took it upon himself to end the war via any means necessary? My god! This is freaking awesome!
At no point in history has a war been covered to that extent in a Pokemon game. It's easily one of the biggest glimpses of the past we've seen in Pokemon history, and it's being told by someone who lived while it happened. If they had focused the story around that bit of lore instead of just having Lysandre use a relic from that time it would have been a lot better.
As for the routes, people like it when there's secrets to be found. You can still have straightforward routes with locked off areas that can be explored later. The problem is X and Y don't have routes like that; they have small, linear routes that don't have anything to find in them. You know how Route 1 is usually a small but interesting route with grass in it? Route 1 here is a short path; not even worthy of being called a route. That might be because it's so urbanized, but even out of the way things like caves are linear with no secret areas or Pokemon. The only area that can be explored is Terminus Cave, and even it doesn't have that much in it aside from Zygarde. The towns don't have much either, in terms of character or places to visit. They're more like goalposts than true, actual towns with their own unique charm. I guess you could blame it on Kalos being very urbanized but Unova was too and it had a lot to explore.