I am ALWAYS happy to meet a new satisfied cruiser. By the way, you made a very good choice for your first cruise, the Haven on Epic is a very nice spot, and you were separated from the hoy palloy.
Epic has a lot of positive attributes, but it is a big and somewhat crowded ship. You made sure you could dine in the Haven's private restaurant (which I have tried and I love it).
THE ENTERTAINMENT ON EPIC MAY BE THE BEST AT SEA. I am partial to "Blue Man Group" however, it is one of my most favorite shows in the world. I actually started recommending it to cruise lines as far back as 1994.
I also think the "Legends at Sea" is one of the best shows I have seen on a cruise ship. I am not sure why they didn't extend it to other NCL ships, my guess is that it was too expensive, but it is good.