I don't know about that... Credit can be very different. A loan that goes up and down is a lot different than one that only goes down. Your installment loans like a car loan or your mortgage are very different from a revolving loan like a credit card. If all you have is credit card debt that you can continue to rack up and increase, then that should send some red flags.
The report didn't say that you had to be carrying ballances on these loans. I've got several accounts showing on my credit report if you count the store accounts like Discount Tire, Gateway, and Best Buy that are all at $0. All of my credit card accounts are paid off every month, so I don't pay finance charges. When I do use one of my store accounts it is only to take advantage of a six, twelve, or eighteen month no interest deal. If you can finance something for no interest then you should do that instead of paying cash. Using cash does nothing for you.
Here is the secret... If you want to improve your credit score without doing a thing different in your spending and paying habits, then here is what you do. Contact your creditors and find out when they report to the credit reporting agencies. Then move your billing cycle to be a week after that date. That way everytime they report your account to the bureaus it will show a ballance that changes. Do this on the accounts that you use. That will help your credit because it will show utilization and ontime payments. Beware though... If you max out your credit cards every month then this is also going to show a very high utilization. The trick is to calculate how you can show a low debt to credit ratio while still showing utilization. That is why I keep my store accounts open even though I hardly ever use them. The eight or ten thousand dollars in available credit that sits there unused offsets the utilization of the cards that I do use. Of course, the card I use mostly now is a charge card that has no limit, so my backup limits are largly just sitting there being open and showing credit history. If you use a charge card then you don't have to do as much calculation. However, when I was using my Delta Skymiles Credit Card for everything, then this was a great way to build credit. I build my credit score 150 points in one year with this as one of my methods. I now sit near 800 and my wife is in the 800s with her score. I am interested to see what it does after the new FICO calculations go into effect...
Credit manipulation is a specialty of mine.
I used to do it for a very large consumer credit repair law firm that I'm sure you have heard of if you have ever looked into that kind of thing. I'll have to write up what I know about this sometime in the future when I've got some time. It really isn't as hard as some people make it out to be. There are just a few tricks that you can utilize that make a massive difference in your FICO score.