As we all know, 1.5 is coming. Here are my ideas: (some obviosly cannot be implemented)
-station and catwalks visible in editor
-shadows on terrain
-allow selection of 4 different staion styles
-enviornment editor allows option of lightin up catwalks
-allow roads, and queues you walk throngh (like how Hper Rails does it)
-optimize, (remove unnesesary suppor caps, etc) especially water reflections
more will come when I think of them