You ask how democratic and fair the reputation system is. I will start by answering that "democratic" and "fair" are not the same thing. This site allows just about anyone to come in and upvote, and not too many fewer to downvote. Allowing just about anyone to vote, while highly democratic, leads to results that may be far from "fair," depending on your sense of that word.
So, while I think all of us can agree that the current system is democratic as far as we understand what democratic is (i.e., near universal participation), how fair is it really? Quite fair!
You have to remember, for every question and corresponding set of answers, there are two considerations:
1) # net votes from the community
2) acceptance by the OP
1) is a measure of how useful an answer is to the community. The reason votes are important is because every answer is visible to the community as a whole. It is searchable, so that when someone needs that answer, it is there. And having the endorsement of the community should imply that the community thought it a very useful answer to the question to which it corresponds.
2) is a measure of how useful an answer is to the OP who asked the question in the first place. Thus, having two separate measures is an acknowledgment that the needs of the OP and those of the community do not always match up. (Frequently, the OP will accept an answer that gets fewer upvotes than others.)
Is this perfect? No! Democracy allows non experts to vote, and they may make bad voting choices. There is a penalty for downvoting, so many people are reluctant to downvote bad answers. Sometimes, as software developers know all too well, the OP has no idea what (s)he wants and accepts an awful answer that reinforces existing prejudices. Another problem may be a built-in bias toward answers from folks with high rep - although I wonder how much of a problem it really is, even if demonstrably true. (Folks need to earn their respect, and those who have consistently provided high quality answers get the benefit of the doubt. Real life works this way.)
That said, it is the best system we have for the purposes of SE: to have a participatory, living knowledge base that draws users to the best questions and answers. In the large, this system works extremely well. Anyone with a math question that knows how to ask it will likely find a very useful answer here.
I took a look at some of your answers to understand the nature of your complaint. The first thing that came to mind is that you need to adopt MathJax: maybe there are useful ideas in those answers, but they are hard to read. (You also come off as uninterested in whether your stuff actually gets read.) I for one will not upvote an answer that requires too much work on my part to translate. (Going through complex math is not work in this sense!)
The second is that sometimes all that is required is a brief answer. Brevity is a virtue, always!! Just because you write a novella does not win you the right to upvotes. Your prose must be readable, and to do that you must draw people in.
Let us consider this answer, for which you got zero votes. (The only other answer got 1. I see you did use MathJax here.) The OP asked a general question couched in a specific example: why do we have to consider branch cuts when computing "this kind of integral" with a square root? In my opinion, the OP was not really asking for the result of evaluating the integral he posted. Rather, he wanted to know why branch cuts were necessary in certain integrals and what effect they have on their evaluation. Your reply was correct insofar as one would evaluate the integral: sometimes you can get rid of branch cuts altogether by substitution. This is very true, but unfortunately it is not useful. The real question was about how to deal with branch cuts in integrals to be evaluated via complex analysis methods. The OP could have used a better example, as there are many in which one cannot easily get rid of multivaluedness, and therefore has to address the choice of a branch cut. So you didn't answer the question. That said, was your answer useful to the larger community? There, I'd also have to say no because your answer will not be found in a search of evaluating integrals with multivalued integrands.
Another one of your answers stands out to me. Here, not only do you not use MathJax, but you close with the line "[l]ater on in the evaluation setting y = sin(t) may well be a promising idea." (Emphasis mine.) Again, you received zero upvotes. In this case, the system worked because stating that something "may be promising" is not a useful answer, ever. Either you've done the problem or you haven't. Guessing along some line without having traveled down that road is not only not useful, but in many cases harmful. I actually would have expected to see downvotes, but zero works too.
My advice if you want to reap the rewards of the system better:
1) Use MathJax.
2) Read the question carefully.
3) Provide a brief, readable answer that completely provides what the OP asks.
4) Don't guess.