Full time job, Baby, GF. I think I have even less time. You can do all that after the main story though. I have 9 hours on it. All main story done. Opened some demon doors and going work on keys now. Doubt it will take me 20 hours to complete all that. I know you can buy all the buildings and stuff. I mean its good the fixed the old time glitch from the last game so you can't disconnect from xbox live and just put your clock forward to get max money and repeat it but there are dupe glitches already that pretty much make up for that.
Also the fact you don't die you simply get knocked over annoys me. Dying in a game adds to the difficulty and as you simply just respawn in a boss fight it ruins the fun. You only need to use a strategy if yout going for the no knock down achievement which even the is easy all you do is roll around when you are low health till it replenishes.
And with COD it is more about multiplayer. Took me 7 hours to complete the game on veteran but the story for me is actually good.
There are far to many game breaking glitches in it for me aswell.