I dont like either the idea of recycling old maps, or returning to nostalgia, like other games did, and we can see how they ended up. (cuz they listen to the "elites" of the game community, game just starts going downhill faster than the titanic xD).
Train is the only 1 cuz its one of the "icons" of CS maps. but in the end.. there is so many, that whatever. I love playing casual maps, its what i do mostly, and if its an active duty pool, its usually on ancient or vertigo. problem is most casual maps get so underplayed, Valve cant take them serious.. so its a risky situation