Collar - Will try the hand stitch method..
Sleeve - There are diagonal lines going from the high front sleeve to the low back sleeve
cuff - The cuffs dont seem to want to close flat though they lay nice and flat if I am not wearing it. I think I remember another post on these forums where a poster recommended stretching the elbow area of the top sleeve.
back vent - I don't know what happened there lol.
Anything else?
Also, when you mean the balance is off, what do you mean? are you saying that I've sewn the right and left side seams differently? I've identified a lot of things thanks to you guys.