I like the narrow paths. The geometry looks just fine to me. I love the skybox. I agree with how you did the RJ; don't change it only to make one person happy and you should know no matter what you do, you are never gonna make everyone happy. I don't think you have to have grass everywhere. I like that as you have it now.
A name is just a name, and people arent going to play or not play your map because of the name, but the 4sky thing is a misnomer for sure. Do these give you any ideas:
sky_flag
4flags
ff_skyplats
sky-high
sky_caps
high_caps
And you don't have to have "ff" in the name. People will know what game they are playing and that the map is for FF
Don't you think you should put some props on the bigger platforms to let attackers/defenders have some cover? They don't have to be huge props. Valve has some neat rock piles that would match your textures just fine.
You gonna put some healthkits evenly in the center somewhere? That's gonna get annoying not being able to heal yourself a little bit when you make it near to center of the map. Maybe cut out 2 of the bags in favor of healthkits?
*Frags*