While the narrative Jak2 was always awkward, it's an excellent game.
Actually I think it's one of the best games SCE has ever released.
It was a feature rich game, with lots of quality content and variety.
It was a platformer, a 3rd person shooter, a sandbox adventure, it had driving sections, skating, plus minigames. All done with proper care.
Technically it was super ambitious for a Ps2 game, with a very detailed open world (compared to what was avaliable at the time), great environmental and character designs plus excellent animations.
Narrative was really the only piece that didn't fit properly...and difficulty felt sometimes unbalaced and frustrating (but it's more or less like any other ND game I would say).