Fluffy may get alot more orange to his ground color as he gets older, but if not, then he's a really nice Miami Phase. It's often difficult to tell with normals since they can change alot as they grow. Either way, he already shows alot more color than the average normal for his age and you are very lucky to own him. Guaranteed, he'll be a stunning specimen as an adult!
Fluffy may be a little intimidated right now in such a large viv. Hopefully, all the "stuff" you have in there will give him a sense of security. Since he's very active, he must feel pretty safe. Corn snakes are often much more active at night than during the day, thus the "misconception" that they are mostly burrowers. An owl would consider me a "burrower" since I rarely get out of my bed once I've gone in! Again, consider yourself lucky to have a corn that tends to follow your time shcedule rather than what nature dictates! Alot of keepers never get to see their corns until after sundown!