I have some ideas but recomindations are fine with me
The HD25-1 ii would be my suggestion. Comfortable/light-weight, great sound, portable, and rugged. I listen to mine everyday and enjoy every second. Especially if you will be using them on and off a bus, I'd think you'd want something durable and light, and the Senns take the cake.
Ultrasone PRO 750 (black & grey version, not the blue)
They have those on Amazon now for $230. Pretty crazy considering their list price was $430. That's a pretty big price decrease.