good day for it eh? i walked down to the carpark on the path you talked about a few months ago and compared to what i rode down about 10 years ago, its changed a lot since then.its probably quicker to ride down but not as gnarly (did i use gnarly on stw ? shame!) just like how the descent down from rothie lodge has been man handled and spoilt over the years.
not sure about where you want to go though, ask dave in bb. he was on about a descent over the back of gorm towards ryvoan or something. said it was good.
this week i might head up the track you started on, around the great slab/alladins couloir and push it up to cairngorm then decend down the back track to the ptarmigan and over to the ridge that takes you down the ciste on creagan dubh. finishing up with a ride up the mountain road. still havent done this.