Played the original Dead Rising recently. I played 2 and its expansions back in the day and thought they were a lot of fun, but for some reason I never picked up the original until it came out on Steam.
Keep in mind that my expectations for games have changed since 2010-2013, so there were quite a lot of 2006-isms that bugged me even if I found the game fun overall.
For starters, I really miss the combo weapon system in 2. Your success in Dead Rising 1 (short of grinding levels) feels really dependent on knowing where all of the powerful weapons are. Guns are actually useful against bosses, unlike 2, but you can't strafe while shooting.
Controls are kinda wonky. I don't like how dodge is by double-tapping the left stick, whereas in 2 it was by clicking the left stick.
Survivor AI is fucking suicidal on top of brain dead, making escort missions more frustrating than they need to be.
Otis can go fuck himself.
The time limit is more strict than I remember the one in 2 being, but that may just be because I maxed out my level in 2.
I can definitely see the more grounded story and setting appeal more to people than the over-the-top gameshow world of 2, but I personally prefer the ridiculous Vegas-type setting of 2. Frank is a more charismatic protagonist than Chuck, I'll admit that much.
I can definitely see why people prefer the original, and I still think it's worth playing, but I still think I had more fun in 2. Then again, before this one I hadn't touched a Dead Rising game since Off The Record in 2011.