In terms of practicality, your taxes this year? Your lifetime taxes? College students? No vote. What happens if I paid a million in taxes last year because I sold my company but nothing this year because I took a year out? Do state taxes count? What about state contracts, do we discount Elon Musks' vote because he receives so many state contracts for his companies like SpaceX? Or do we worry that Elon Musk gets tonnes of political power which he then uses to pressure the government into.. awarded him more SpaceX contracts? Those paying the most taxes are by definition those who have benefitted most from a well run country, surely they be penalized not given more power?
To your second point; lifetime seems fair to me. Should college kids’ votes count as much as someone’s with more life experience? It doesn’t seem intuitive to me.
I get the plain “all humans are created equal” argument from an ethical perspective, but I don’t think this goes quite that deep. I would see this more as a tuning parameter for the efficiency of this system in the same way that criminal sentencing or any concensus based model we have where certain people have more “say” in it.
In a Christian sense, which you might find jarring, I’d regard the “all humans are equal” part a rule made by God, and “some humans should be given more decision power” a rule made by us that in no way contradicts God’s ultimate will.