This is an interesting dillemna. Elected positions of power do have some prestige to them, which is worth something to encourage people to apply for the job (i.e., run for election). From sitting on the front row of this, I think my spouse was fairly compensated for her work as a city councilmember for a small-ish city (~30K residents). Her takehome pay was paltry, but she did get decent medical benefits, which was worth far more than what she was paid. And how much work each councilmember put in varied a great deal. On her way out she worked to get the number increased (for those who followed her, not for her), which I think did result in people who might otherwise have felt they couldn't afford to to do it stepping up and running for (and in at least one case winning) the job. My wife really liked the work and became interested in moving up in elected life, which resulted in her putting a lot of work into what she was doing. There are other people who barely bother to read their packet before showing up at a meeting.
Moving up the ladder in elected life meant moving into a position that was a full-time, paid like a real job, position. Which seems fair. And the pay is low, but not embarassingly so. I think that's true of congress, too (and judges). The pay is low for the work performed, but not embarassingly so. That means that most people who try to do it are willing to take the pay cut. That also means that it is people who can afford the pay cut (i.e., have the money coming from somewhere else) who fill most of those positions. I think that is detrimental because it does result in a skewed pool of applicants and job holders.
How to fix it? I think the wages should be increased. How much is the question, and I'm not sure what the right answer is.