Pedestrian completion ratio + high TD/attempt ratio says to me that there's a high proportion of long passes being attempted. In the end, like twobyc says, if we're getting a lot of TDs (coupled with few INTs) from the passing attack then the results are acceptable.
The thing is that all the completions for touchdowns were from 20 yards and in with most of them being goal-to-go passes. I think the low completion ratio does indicate more throws deep. All of the receivers had 12+ yards per reception which would strengthen that assumption.
I think it's important to understand that these scrimmages probably don't play out with strict game-like action. They may have came into the scrimmage wanting to work the deep play action. Considering the amount of runs and bigger yards per completion in the passing game, I think that was the case. In goal-to-go and situational drills in goal-to-go, I think it was apparent that they wanted to work on passing the ball down there.
These are good things to be working on because I think the structure of this team needs to exploit the pure speed we have at receiver and effective passing in the redzone has always been a deficiency for us. We don't know right now if we have a guy like TR or MI who has a great nose for the end zone, so being able to pass for touchdowns down there is certainly something important.