The old missions system was very diverse. Each mission was a mini-game in its own right. We were dealing with unique NPCs and Items. The stories were very memorable. The sensation of achievement was great. The contrast couldn't be bigger.
The stories in these new missions are just as forgettable as in the crimes. Guess what you'll be doing today? Yep, you guessed it: Beat up another slacker. Sometimes they are decent mugging / level targets, but that's about all I can say in favor of these new missions.
You do realise that duke's missions are just the first (and simplest) in what will hopefully be a wide variety of NPC-assigned missions don't you?
As for the stories of the old missions being "memorable" or those missions themselves giving a sense of achievement, well many of the old missions were simply beat-em-ups against an NPC and the ones that weren't were pretty straight forward really (certainly not a memorable "experience" imo).
I've been getting about 8 of the same missions from Duke, ranging from "easy" to "hard", all at about the same difficulty level. It's getting a bit monotonous.
oops. you all have triggered my -- "How did I miss this game all these years!" ... feel.