The "profit" I referred to was specifically for the printing of cash. And who exactly is in debt when that happens? The bank got legal tender worth exactly the amount it exchanged for it. The Treasury had it's printing costs covered. The Federal Reserve made a small profit on the transaction. This difference in money doesn't just disappear, it gets used to cover the operating expenses of the Federal Reserve Bank, it is used to buy and sell securities, etc, it ends up out in the economy.
I'm not sure where your idea that profit = interest comes from, do you feel like you are in debt to the local grocery store whenever you buy food for more than it cost them to get it? Maybe we're using a different definition here and it's simply a semantic difference we have here, but I don't see who is in debt to who in the case of printing cash (which is a small part of the situation anyway). Cash is essentially interest free money from the government. But you have to be careful about how much of that you issue or you end up with huge amounts of inflation.
As to the dollar losing 95% of it's value, that's a natural consequence of the economy expanding. You have to have some inflation in order for the economy as a whole to grow, and it's nearly impossible, under any monetary policy, to perfectly control inflation. You are aware that under the Gold Standard, the value of the dollar went through many wild fluctuations. Sometimes as a result of new gold being discovered (value went down), and at other times as a result of there not being enough of it to cover the economic expansion occurring (value goes up). Inflation as a whole is not necessarily bad, as long as wages keep pace.
I absolutely agree with you on the problems of the rich getting richer, and the poor getting poorer, but I'm not sure I think the blame for that can be laid at the feet of the Federal Reserve or more basically the monetary system of the United States. The problems it seems to be stem more from poor stewardship of the economy by congress and the presidents. Monetary policy, which the Fed is at least partly in charge of, is only one part of the economy, and can only effect things so much. Spending by congress, laws regulating industries, education, infrastructure, tax policy, all of these things are much more likely to effect the wage gap, and the loss of real wages by middle and lower class Americans, and none of them are under the control of the Federal Reserve.
Finally, you can certainly criticize the Federal Reserve for not doing a good enough job at it's primary purposes, controlling inflation and keeping employment steady, but the blame for that likely lies more with the people who have been in charge than necessarily with the system as a whole. Further, returning to the gold standard, or some other monetary system wouldn't necessarily magically fix these problems. Regulating an economy as big as that of the United States (especially now, with all of the ties around the world), is a very, very, difficult job. I for one, like the idea that the Federal Reserve, as a quasi-private entity, that is self funding, with governing board appointments that rotate and last long enough to not let any one president or congress "pack the board," is in charge of some of these aspects of the economy, so it's at least somewhat insulated from politics (but ultimately always accountable to congress).