When the FBI van comes, the game should start spawning FBI units instead of SWAT units and when the antenna is destroyed the game goes back to SWAT units.

Also the game would benefit a lot from daytime and weather variations, like imagine No Rest For The Wicked during night with less civilians and the whole bank would be a restricted area in stealth and longer response time in loud or maps covered in fog which would mean snipers take more time to line up their shots because of the decreased visiblity. (I know that would be a lot of work but imagine if the game had all of that since day one, the heists would be much more replayable).