I could go into details, but its probably too complicated for you.
I can tell you that Zeke it will 100% be dependent on the Oline play. He has little abilities on his own if there arent monster holes. I can also tell you either way that he wont be worth 18 million whatever he does. I can also tell you the odds of the Oline being great all year are around 50% on the high end.
Dak will also be dependent somewhat on the Oline. Now Dak can have a great year without a great run game, but he would need the line to pass block well. Probably not going to happen if the line doesnt run block well, however.
If the line is healthy and having a good season then the offense and the team should have a good year.
Injuries are hard to predict.
LVE? If he doesnt get injured he will maintain his slightly above JAG type efforts.
Then there is the coaching element. Will Moore continue to run Zeke up the middle or will he use Pollard much more and feature him more? Hard to predict these type of things. Featuring Pollard more would really help the offense. My guess is he will continue to feature Zeke.
And finally...............NO! They will ALL not have a great year.