It's tough judging DCL = like Davies, (and Dowell, Lookman, Barkley, Kenny before that) - because I think we want them to do well because it's a nice story to have a local or English player for not much of a transfer fee coming through and making it big. In DCL's case it will be even nicer as he works hard and seems to be really dedicated to fitness and improvement.
The big difference for me in this criticism of him missing chances, is that even top strikers miss easier chances, but they have 2-3 chances per game with better supply of assists and key passes - or more if you're Man City - and therefore they score one. Then the really top ones, score from 1 chance in an entire game, when it's a defensive tactical battle in a CL match for instance. So DCL has got to make 2 steps up first - take 1 out of 2/3 chances, and then hit the target with every chance he gets, while making more intelligent runs and movement to create space for himself. And then finally, he has to be a striker who can make chances out of nothing. But then we're talking about an elite skill that only a few players have, so while we're waiting for him to develop, or for money to buy a much better striker, we may as well support him and see how he goes!