I was there last night too. Pretty mobbed. The line for Grimore got up to 75 minutes, and nearly went all the way up to the Western Gate and back down again, while the line for Pony Express nearly reached Wilderness Broiler... making it pretty crazy to get down through that walkway.
We've been arriving between 5-5:30 to avoid traffic and parking (and coming from LA, taking the Knott exit, not Beach), and it's worked out well. We just meander and sit in the Marketplace for a bit, maybe grab a bite to eat and wait it out.
Since we have the season pass, we had already done all the mazes, so we did a few, watched a show, and then focused on finding all the lantern spots, thanks to this guide from Knott's Network. Many are very cool, especially the ones by Ghost Town train tracks, center of Forsaken Lake, and by Jaguar!
However, we couldn't get any major lantern interactive effect at the other Forsaken Lake spot (by Log Ride) aside from just having the light turn blue, and couldn't find anything in The Gauntlet or the by the Main Gate (though admittedly, we didn't look too hard at the Main Gate due to crowds). Anyone know more? We even asked employees about The Gauntlet location, and they didn't know anything about it either.