I think what surprised me most about revisiting Halo 2 was how, out of everything, the thing that held up the best was the narrative and world building. Which isn't to say that the moment to moment gameplay hasn't been improved from the first game, but the writing really does deserve a huge amount of credit for managing to take the handful of lore pieces from the first game and constructing what feels like a true epic. Not just and epic in the sense of "the explosions were very big and cool" but in the sense of this feeling like an ever expanding and grand tale of two warring factions and an ancient race that's caused it all.

But while the story is a definite improvement the gameplay still occasionally falls into the same traps of the previous game. Nothing as bad as the second half of Halo, but fighting the flood is still kind of annoying, and the streamlined level design can make certain fights feel claustrophobic. But still, generally, Halo 2 does a better job at balancing the difficulty than it's predecessor.

If you've been thinking about revisiting this (or hell, even if you've never played it) than I can safely say that Halo 2 is still a good game without the need for rose tinted glasses, just don't be surprised if it's something other than the gameplay that hooks you this time.