They're not silly questions at all!It's good that you care enough about your little guy to ask.
You can overfeed your snake, and because KSBs are desert snakes they are built to go for longer periods of time without food and water. However, like you pointed out, since he's growing and just came through a shed cycle, I'm sure he feels pretty hungry! I would still try to stick to the once a week routine, but if he seems really hungry, I don't think it would hurt him to be fed a little extra every once and awhile.
That's so cute that he's gotten used to you holding him to drink and I have heard of others that do this, but I would just keep an eye on it. I'm not 100% sure about KSBs, but I know with other desert-dwelling snakes like rosy boas that if they drink too much after eating it can cause them to regurgitate. If you haven't had any problems with him yet then I wouldn't worry about it, and of course you don't want him to get dehydrated, but maybe only let him drink every other day instead of every day, something like that. If he's been with you awhile then he should know where the water dish is.