Well
If it didn't take forever cause you didn't notice who you were supposed to shoot (The people that were killing the hostages) and then failing and having to restart again, it'd be generally be smooth all-throughout... I reccomend flashing "HOSTAGES" or something like that so we know that there are hostages that will be killed during that scene... It's fresh new work though, I don't remember the last time we had a shooter...
One more thing, why do we keep switching guns if everything kills everyone in one hit anyway?