The main issue was passing.
I'm fairly slow, so YMMV. My best laps were in the 2:06's on my hard street tires. Others complained that the track was quite slick.
Here's how it worked last weekend.
Green - novice
Blue - intermediate (some experience but new to this track)
Red - experienced (been on this track before)
Each group ran alone in the morning. In the afternoon they had a session that was Green+Blue. Late afternoon they had open sessions.
They accepted entries for 60 cars, but this day was not fully subscribed so the track was not crowded.
Passing was restricted to two places (drag strip, between 4-5) in the morning, added a third (between 8-9) in the afternoon. I was one of the slower cars in Blue, faster only than the Triumph and a couple Miatas. In the afternoon while running with Green group cars, I had no issues being held up. The Corvettes in Green were all slower than the Miatas in Blue and I was passing them 2 and 3 at a time on the drag strip, so clearly they were paying attention.
With only 60 cars at HPR we should be spread out a bit more.