I've never played Dead Rising, but what I think what would be cool, in a zombie themed game is what I mentioned further up regarding "The Walking Dead". Using hordes of zombies to direct the player in specific directions. I don't know if you've ever seen the show, but the tank scene and the events of that episode (first or second in the series, I don't remember, I binge watch! That's what Google is for) probably best describe the scenario I'm talking about. Kill a few closest to you, but get the hell away from them! I think it would be an excellent way to deliver some sort of linearity/direction to an otherwise "open" world.
EDIT: Thanks, Conjured Entertainment for showing me that I misspelled "hordes" originally, it's corrected now, but obviously not in any quotes from me. In my own defense, I had a few beers in me! Stuff like that really bothers me for some reason (OCD?)! Homonyms do get past the spell checker, though, unfortunately.
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