1) We lost BY FAR the most effective WR in Palmer, and most of the returning WR's are unproven
2) Washington has been injured, first it was a broken hand, then it was another injury after he came back to practice. Nobody knows how he is doing, or how much of Palmer's production he will be able to replace.
3) Billy Kemp IV is mainly a possession receiver. That's great to have, but it's unlikely he will produce big plays.
4) Fleeks was supposed to be a positive, veteran influence, and he came in so overweight he couldn't practice.
5) ICG is an unknown, considering how quickly left the team last year
6) Many people (not me) thought Malachi Coleman would be able to contribute to the WR group this year, but it sounds like he is nowhere near seeing the field, and other true freshman receivers are ahead of him.
7) Having to count on walk-on receivers is fine for a game or two, but those guys are unlikely to be big-play threats and be difference makers on the field.
I am sure others have concerns of their own.