If you take the park route on day 2, you're gonna wanna do the superman on your bike coming down the smithville hill - like that guy on the fixie in that now famous video
Pretty sure that's where I hit my max speed of 38 mph (according to Strava).
But in all seriousness, be VERY mindful of the riders around you in the park. With so many ups and downs, many people don't know how to properly descend and lose control and run into people - or can't make the climbs well enough. I've done this ride 4 times, and almost each time there's been a major injury in the park. Our first year they stopped the regular route people because an ambulance and a medivac chopper had to get through into the park to airlift someone out who crashed.
I've been fortunate enough to leave early with my VIP friends at the front, but if you leave later at the back of the pack you'll be surrounded by a bunch of inexperienced people who think they can do whatever. So, just be careful.