To me, this would have been way more interesting without your bros posing in the shot - particularly if you had managed to get the train to stretch all the way to the vanishing point. I'm pretty much a newbie here, though, so take my comments with a grain of salt - just 'cause I'm being critical doesn't mean I think MY stuff is doing any better! You'll likely lap my submission... Good luck!
** Came back to bump you up an extra point & add that I think this probably would have been an awesome shot (to me anyway) if you had them line up, evenly spaced down that yellow line. I realize you may not have actually known them and may have felt you couldn't have done that - but that's part of being a photographer sometimes!**
Sorry, I don't get the title, as those lines (the light above and the yellow safe line) are not a strong diagonal driving the image. Is "Diagonal" the name of their band?
I like the movement given by the train behind, but it looks that some of their faces are fuzzy.