There are exploration paths all over IOA, path down by the lagoon in Toon Lagoon for instance...there is also a path that goes down by the lagoon in LC, you can actually hear a troll under the bridge...and of course Sneech Beach..As for the Studios there is the control room tour at Twister (must ask) and Immigration Tour at MIB (must ask)...The control room for Cinnematic Spectacular is in Richter Burgers...I wonder if they'd let you in for a tour if you asked, can someone ask??
Outside of Hard Rock there is a butterfly garden, very quiet and secluded area, very nice..
I'm sure many know about these areas already haha