I just recently returned from spending 10 days up there and let me start off by saying that the resort *exceeded* my expectations. You are aware that Crankworx is going on up there from the 10-19 correct? Consequently, various trails will be closed & lift access will be curtailed on certain days.
Depending on how much effort you’re willing to put in and what you like riding, Comfortably Numb, A River Runs Through It and Lord of the Squirrels are considered the must do “legendary” rides up there. Lord of the Squirrels is relatively new but for anybody that rides away from the mountain, it’s kind of the hot new ride. It’s about 15-17 miles depending on what route you take and expect 4000-5000 feet of climbing. The Lord of the Squirrels downhill portion is phenomenal if you like fast, tight, twisty, chunky singletrack. A River Runs Through It is essentially an Intermediate trail that runs along and through a creek/streambed area in a twisty fashion that is so constant, I won’t sure which direction I was going most of the time. Signage was great thought and Trailforks is your friend. Consequently, there is tons of wood features to keep you out of the water and wet areas. IT WAS A BLAST but I like that techy stuff.
Make sure you do the Top of the World ride in the park. They only let 200 people per day (I also heard 150) ride this trail to keep it in great shape. If you want an adventure AND are comfortable riding in the backcountry where help will be hours away (we saw ZERO other riders) AND will have company, look into taking the Khyber Pass turnoff from Top of the World. Otherwise, stay om the trail and it will take you down to the Ceeekside gondola.