The badly worded question issue is clearly major, but it's received so much publicity, and with meta pollers like 538 existing it seems like it shouldn't be a huge problem when there's such a wide selection of big money polls available. All those ideas seem decent, but as you said they're not really solving the problem, just inching you toward a less biased sample. I'm sure people that already declined to take the poll are real happy to be bothered again about it. As far as I can tell the only way to actually make polling work is to force people to respond, and obviously that won't happen. And even if it did people would give troll answers(at school we had captive polls and the last question was always "how seriously did you take this poll?" of course the least serious people always marked themselves as most serious). Even paying people to respond biases the sample because now you're more likely to get people who want money(not necessarily totally correlated with income). Of course you can infer that your sample is biased by one side being more enthusiastic, but without a way to enumerate how biased you're nowhere.