I understand what you're saying, but it could backfire also. If you let him score too much, how will he take it when he has a game (or two or three) where there's good defenders, a good keeper, or he's just not quite "on"? When my son was that age, one season his team won every game. And yes, he was the top goal scorer for his team. The first game of the next season they lost. He came off the field crying because they lost. He didn't know how to accept the loss. I'm not saying what you're doing is wrong. In fact, you're right, confidence is a big factor. I totally agree with that. But it needs to be tempered with realism.
One thing you can do with your kid that--much like dribbling--is the sort of thing you really can't do too much of is playing informal soccer tennis. It's a great way to learn ball control, how to receive the ball, work on first touch, etc. Obviously you can let the ball bounce first, but it's a very low-impact, laid-back form of 'training' that can double as good parent-child bonding time, like playing catch in the front yard.
Part of my plan is to train him every year to the game that exists for the upcoming year. For ex, U6 and U8 have a small field and 6' puggs. No goalie. So how do you win in that game? It is quite different than regular soccer. I want the kids to focus on dribbling and trying to score. When there is a goalie then it becomes a slightly different game. So there might be more shooting from distance, chipping over the goalie, more passing and crossing, etc. He has lost a few games so far. He seems to handle it ok when it is against kids, but he still cannot handle losing against me. Throws a huge fit. He is a bit spoiled to be honest.