How consistent are you being with your expectations and the consequences? When he hits or kicks you guys does he get a different reaction based on how stressed out you are? When you give a consequence is it from frustration or is it a predictable one each time? Consistency can really make a big difference for a lot of kids. If you have tried consequences sometimes but they are generally only put into place when you are frustrated then you may need to find something that is consistent and you can stick with for a month. A few unrelated moments of giving a consequence in the heat of the moment is not going to change long term behavior.
Keep in mind that it is very normal to have times when you question what you are doing and if it is right though. It sounds like you had a big scare, but really your son probably would have wanted to find out what would happen when he played with the cords even if you smacked him every time he went near them. Kids do the craziest things just because they wanted to see what would happen and it doesn't really have anything to do with parenting style. If you have been mostly happy with parenting until this moment then I think you should continue on as you are doing right now. If you still feel the need for a change in a few weeks, after you have gotten over the electrocution, then you should look for changes to make.