Nuss has Mutiple issues going on. More so, I think it's correct to say LSU has multiple issues going on with its offense. For starters, the play calling was bad. Last season I got the feeling that the players had to significantly out play the play calling. Another issue is their WR corps were greatly overrated. Even Mason Taylor really struggled to get separation against man to man, and against zone he wasn't finding the soft spots. Throw in Nuss trying to "make things happen" and it's a recipe for exactly what happened all year. Nuss has to learn to often take what the defense gives him. That's the 1 thing I that really drove me nuts about him. He was always trying to force plays, some because of play calling, some because of lack of receiving talent and some because of "trying to hard".
On the flip side of that, he's also done some things you don't often see QB's in college do, like throw open receivers. He did that several times which unfortunately played into his daring role of forcing things.
If he can learn when to force and throw open receivers vs when to (and often) take what the defense gives him, I think we'll see big leaps this year. If he can get some better receiving talent around him also that would be extremely helpful for his progress in learning when to force things. But as of the end of the year, they didn't have any receiving talent that's worthy of a 1st or 2nd round pick in the draft. Which is insane considering every single draft the best 5 QB's typically have 1 guy going in the 1st round or high 2nd round.