RE5 is a joke. The only time anyone should ever die playing the campaign in that game is from missing a quicktime event.
I was disappointed that they didn't put any extra characters in the merc's mini-game, just re-skins of the main characters. That was the best part about the minigame in RE4, playing as different characters.
And the simple reason behind getting rid of the classic zombies is because they're too slow. Imagine shooting zombies moving as slow as the RE1/2/3 zombies, but actually being able to hit them with every shot. The plot is just stupid as hell now, so you may as well just ignore that part of considering why they're not there anymore.
"An Air Force A-10 Thunderbolt II flew a show of force and expended flares for emphasis over Salerno after enemy forces attacked a coalition forward base. The arrival of the aircraft prompted an immediate retreat by enemy personnel."