The campsite above the waterfall is much nicer (grassy knoll with rock walls) and you will easily get there in a day from the carpark at Rasberry. From there only a few hours up to Bevan Col. Very much doubt the hut would be full in November, plus guiding companies have spare tents stashed there so they are obliged to camp if the hut gets full of private climbers. Yeh any solid boot that takes a crampon safely will be fine. Up and down the Ramp is fine as long as you are prepared to either go slow (pitching) or once you cross the schrund at the bottom of the Ramp then go solo on 50 degree terrain. Usually firm in the mornings. In the late arvo it turns to poo so either you need to be a confident decsender or same again, pitch or rap for safety. What kills people is moving as a roped party on steep terrain, with no running belays in and usually with either icy conditions (easy to slide) or soft conditions (self arrest isn't worth diddly in these conditions so trying to pull a mate up, let alone yourself is near impossible. I would still do a recce on the standard NW Ridge route so that one) you know the way down, 2) you can go up the Ramp in firmer (and faster) conditions and do a traverse by descending a different way (remember the fluro yellow gaffer tape you placed earlier on the recce!!!). As far as bivy bags go, if you carry it...YOU WILL BIVY!!!!! Be careful with your hire car at Rasberry as there have been a lot of break ins over the years...
Steve
P.S...Can't help you with the speeding fines!!! Bro!!!