Again this atmosphere thing, we have something like 40K plus season tickets, one of the largest in the country, I would take a bet that a vast majority of those don't sing during the game, what are you going to do with those fans?
And if your talking of creating atmosphere like in German games, well that's an utter crock, nothing worse than forced and fake atmosphere.
A vast majority of the new seats will be for regular fans and the rest will be corporate, and thus I am not sure what the issue is.
8K extra seats will create atmosphere but it's what happens on the pitch that does that.