I feel ya, bro. However, I don't think I explained myself clearly enough. I'm not talking about a fully unlockable class with every weapon in the game eventually being available. I'm talking about some very basic starting weapons and that's all.
As for the story, it can still be hidden to where you don't know what's going on fully, but have some type of reveal at the end of the map that answers a few questions and sets up the next map that is being unlocked.
Also, like I said, there would still be the option of having a "Classic" game mode where everything remains the same from previous Call of Duty Zombies installments. However, if you're talking about a full game of nothing but Zombies, you gotta mix it up and add more features. If not, Treyarch would be better off just continuing to add Zombies as a game mode to their standard Call of Duty games.
Ok, I see what you're saying now. I had to re-read your first post haha. The more I think about it, the more I realize that it is a good idea. So like have 3 or so weapons from WWII, 3 from Cold War and 3 from Modern, and play through the maps listed under each era, unlocking later ones. Classic zombies would be good, and now that you clarified your cutscene idea, I think that would be cool. So, have cutscenes at certain rounds just to almost confuse people, then have them search the map for answers? That'd be awesome, and it would make the storyline even more involving.
Exactly. I was thinking sort of like Gears of War where you can change your starting character and weapon but your choices are very limited. The main weapons and power ups are still on the map and must be gained by fighting your way to their position. I really think there's a ton of things you could do to make CoD Zombies a standalone game that people would buy in high volume.