The things that stand out are that you really only have one passer who is above average, meaning you might not be getting that many open looks. You also have a lack of ATH in your shooters, which is arguably the most important skill to have a good shooter.
Also BH is more important than you would think for shooters, which is probably one reason that Speller doesn't shoot very well, even though at first glance you might think he'd be your best outside shooter. Almost all my SGs with bad BH skill numbers have been poor shooters.
Most of the above is grasping at straws though. The bottom line is that in HD, it is very difficult to predict how shooters will perform. I could fill a lot of teams with the great SGs I've had that shot 30% during their JR or SR seasons.