These are great filters to make sure polls csn be based on real accounts only. Can I suggest another filter - last posted x days ago. That will help to eliminate inactive accounts.
Also, my two cents worth thinks this will allow the poll owner to control the poll outcome by playing with the filters, unless they declare in advance which filters will be applied. Understand you want to make the dapp more inclusive and more people to use it, but it just seems kind of odd to allow people to vote, and then exclude their vote or opinion afterwards. Afterall, in all real life votes, you always set the criteria beforehand and not afterwards.
We avoid implementing off-chain rules. If the poll owner want to make a decision, they can add an info the poll that “minimum rep N is required for a valid vote”. Actually we adready seen @shaka followed this practice in his latest poll.