Hey man. Welcome.
Sounds like you have a wide range of workout in your routine. So that seems good to me. I would say maybe incorporate a small bit of arm stuff into every other day.. maybe a Mon/Wed/Fri thing. (Since you say you want to be working those a bit more)
As for the junk food bulking up.. sometimes I think that's probably the bad way to do it. It IS bulk.. but its bad bulk. You might want to find ways to feed your muscles with good nutrients as much as you can, as even eating healthier probably wouldn't make that huge of a difference than filling up with junk.
That being said.. I would take what I say as simply helpful opinion, as I am 6'4 yet weigh the same as you. hah. So obviously I haven't yet discovered the proper way to build MY muscle..
Anyway, welcome. Look around, hopefully you can find some information or workouts that you can incorporate into your weekly routine.