The bottom line is that the FICO system is rigged. Anything negative you do will be held against you for a decade or so, but anything positive you do will be ignored. You are FAR from alone in your experience.
In my credit history, I have less than $1000 in charge-offs. That's it. No repos, no foreclosures, no judgments. A year ago, my credit score was around 580. Since then I have a credit card I pay on time every month; a couple months ago, I got a credit card, which I also pay on time.
Today my score is 575. A year from now, I figure it will be 570 or so, even if I pay all my bills on time. Unless, of course, I'm late on something, in which case they'll probably drop it to 530 or so.
Now I'm sure people will come along and tell me I'm being "negative" and "discouraging," but figures don't lie. And, as Robert A. Heinlein once remarked, if it can be expressed in figures, it's fact, if it can't, it's opinion.
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in a credit-scoring postnuclear Stone Age...