His stats will be terrible and he'll take a ton of sacks. In fact, whoever is back there will take a ton of sacks. Our WR's are the league's worst at gaining separation and our OL is a horror story. On top of that, we won't be able to run well.
Allen will have to prove to me that his inaccuracy can be fixed. According to PFF, his accuracy even in short areas were much less accurate than most college QB's. I'm pulling for a turnaround there, but I have my doubts.
The good news is that we still have all of our 2019 draft picks and will have a ton of money to spend on FA's next year so we can fix these problems.