If they don't open the offense up it's a huge mistake IMO. Winston just isn't a game manager QB. He's a gun slinger. That can lead to some turnovers, but it also can lead to explosive plays. And DA said in his opening press conference that he wanted an offense that made explosive plays so I think we will see it opened up more.
And, if they don't want to open it up and take shots down field, then they need to go get another QB now. Trying to fit Winston into a low volume running game oriented offense just doesn't make sense. It's square peg in round hole stuff.
But, I do think the conservative approach last year had as much to do with the lack of any options at WR as much as putting the cuffs on Winston. I don't think Winston trusted any of his WRs and it showed in his hesitancy to throw over the middle or make relatively risk throws. So, I think he has to get over that, the offense needs to be opened up, and they need to add some weapons that Winston has more confidence in. Then again, any QB is going to need more weapons than we currently have.