It is better with the stays. If you were going to go stay-less then I'd lengthen by .25". I think Luxire's unfused cutaway collars look great without stays, myself, but everyone has their own preference of couse. I posted a picture of my collar some time ago in this thread.
Not sure about the button, is the collar too big? Probably best to ask the experts at Luxire itself.
Yes I also went down, I don't have much to add other than I was hoping for a slightly better discount than the $450 for most suits, which isn't much of a saving over the 2 for 1K deal, or the recent 30% off sale they had.I think the $250 jackets are the best thing there.