Maybe you could try to think about it a little differently. Think of yourself as a foreign language translator. Your job is to translate what you have done in your homeschool, into words and numbers that colleges understand. Your job isn't to change your homeschool - just do what works for you. You job is only to translate your experiences (whatever they are) into the "love language" of colleges.
I know that some colleges don't mind a narrative explanation of a homeschool. I went to a Christian college fair last Monday, and there were a handful of colleges where 15-20% of their student body had been homeschooled. Those admissions people talked about narrative records in a very warm and open way. This weekend I'm going to a Homeschool College Fair, and I'm sure it will be equally welcoming to all sorts of homeschool records (otherwise they probably wouldn't be at a fair just for homeschoolers, right?) But I think the majority of colleges may not understand anything other than a transcript because it will seem like a foreign language to them.
You might want to just group your student's learning experiences together into groups that are approximately 1 credit worth. Label it something that sounds like a class title. Once he has put in a year's worth of math work, for example, you could call it "discrete math" or "concepts in math" or something. You could look at CLEP exams, and see which ones look like academic content that your student has learned, and then list those subject names on your transcript. Have you looked at Barb Shelton's Homeschool Form-U-La book? Her book is not for everyone, but she does have a good explanation of how to take what you have done and explaining it in college-friendly language.
I hope that helps.