I'm not worshipping anybody, putin, just asking for honest descriptions. Good grief, is that so objectionable? I often get the impression from you that you have only two views of anything -- awesome, or evil. If anybody defends something, he thinks it's awesome. If he says anything bad about it, he thinks it's evil. There is no such thing as nuance or shades of gray.
So, let's take up your points:
*Secretive
Yes, this is true. I didn't deny it.
*anti-democratic
Not really. Whether to ratify the constitution was left up to an unprecedentedly popular process. You might say, well, the people AT the convention weren't elected. And that's true, but since it didn't go into effect unless it was ratified, the point is not that important. And you have to realize too that it's not like there was any hope of having a convention elected. The forces opposing a federal/national government were powerful enough that no such thing could have happened.
So, writing the thing had to be somewhat clandestine, but ratifying it was as unclandestine as could be, and as popular as anything had been perhaps ever, and certainly in a long long time.
*illegal
Eh, kind of. That's a gray area. One thing for sure is that nobody delegated them the power to say that their document was going to go into effect if 9 states agreed to it. But again, once 9 states do in fact call conventions and agree to it, then they're kind of authorizing that post facto.
*completely overthrew the existing government.
Duh.
*To make it easier to collect debts.
This is the kind of lack of nuance you expect from a Communist. Certainly debt collection was one of the biggest concerns of the people behind the Constitution -- but that was in a much broader context. They realized (or anyway believed) that if America's credit and national defense were allowed to collapse, the colonies would be thirteen struggling, independent colonies that would be easily picked off by European powers. I think they made the case pretty compellingly.
*Didn't want no Shays rebellion and foreclosure relief.
Well, they certainly didn't want no Shays rebellion. Foreclosure relief, as you term it (really, allocation of war debt repayments), was to remain controversial even among those who would go on to run the government. Certainly Hamilton -- one of the least influential people at the Constitutional convention in practice, by the way -- took the position you suggest, and ended up winning the day as Treasury Secretary, by compromising on the location of the capital among other things.
I personally think he was a genius and among the people most single-handedly responsible for the long-term survival of the US, but that's for another day.