I literally have no complaints about this game as of now.
It's awesome, Krypt included. Sure, you might not get what you want right away, but I'd rather have unlockables to look forward to over time rather than simply having it all unlocked quickly or instantly, gives more incentive to continue playing the single player modes and boosts replayability in a way.
And, it's not as if you aren't getting something when you open chests, maybe its not for the character you want, oh well, use what you get for your AI characters which you can then use for AI battles/ToT to unlock more stuff.
This game is supposed to last years, so I understand the purpose of a time/grind barrier to unlocking items in this game.
Exploring the Krypt really makes me appreciate how much work went into this game, there's enough depth to the Krypt that they could've shipped the game without a story mode and I wouldn't have noticed. NRS really goes all out with everything from content, presentation, and gameplay. Think they have a classic with this one.