While the new art is a far cry from the old, I still like it. It looks great in foil. I don't know why they omitted flavor text this time since there's plenty of space for it. I own and play with both versions.

Where Niv-Mizzet, the Firemind truly shines is as a Commander. Fill your deck with cards like Timetwister, Wheel of Fortune, Windfall, and Winds of Change and you will be doing a lot of damage for very little mana. And in Thought Reflection or Consecrated Sphinx and you have a ridiculous amount of draw and damage.

My personal favorite combo with Niv is Mindmoil + Dream Halls or Omniscience. You can cycle your hand indefinitely for free resulting in near infinite damage from Niv.

Besides Curiosity you can use Ophidian Eye, Tandem Lookout/a... (see all)