Well sure, most games have budget constraints.
I thought those FPS games had good story modes? I don't play them. Is that not the case?
Yes, Call of Duty has an awesome story mode - which lasts about 5 hours.
Anyways, GoW3 probably has a bigger budget than most. It will have been in development how long by the time it ships?
Depends on when it started, really. I'm not sure, but I think they started later than most people expect, particularly since Heavenly Sword was also Sony sponsored.
Even with constraints, why put all the resources into singleplayer? This is the connected age. If they dedicate 25% of the staff to multiplayer, does that necessarily mean the singleplayer will come up short?
Hey I'm not saying it's not possible to do any online. They couuld make an online colosseum mode with gladiator style fighting in various forms that could work quite well - you could combine this to do free for all, 2 player co-op (chained together), team co-op (think gladiator the movie style combat, or a group of players against a group of monsters), and the monsters could be player controlled as well for team competition, etc.
In terms of co-op campaign, I was challenged by the impossible idea that Kratos would work together with someone, and I came up with a Red Sonja style co-op experience (Red Sonja working together with a man was after all almost equally unlikely as Kratos working together with anyone at all, so it seems a good fit), where Kratos finds a female version who he simply can't beat (to keep the adult theme, preferably they at some point have sex, and later discover they are twins or something
). This would make for a great tutorial level where you first instead of working together fight each other, but you're both invincible and your stamina runs out at the same speed no matter what, but you progress through the level by performing certain attacks.
These two additions I would actually enjoy. However, what I am expecting is a PS3 version of God of War almost exactly matched, but with trophies and incredible graphics, and I would be more than satisfied with that as well (maybe some online leaderboards for points and time trials or something). That's really enough, and that's all I wanted to say - there's nothing wrong with using that 25% to polish the game rather than add online gameplay. I would probably consider any online gameplay as a separate game and maybe even just sell it on PSN or add it as DLC and have an additional team with its own budget work on it.