How would financing these projects work? Would taxation be on a street level, too? Are you willing to pay for everything that your street needs? A new traffic light or fixing pitholes sounds cheap, but it does get expensive as you scale up. I had to replace four 5x5-foot squares of sidewalk in front of my house a few years ago, and it cost me $5k. Imagine how much it would cost to re-pave a road for an entire block.
Voting purely for your own self-interest is also a double-edged sword. How sure are you that your neighbors will vote to pay for fixing a ruptured pipe that is next to your house if it doesn’t impact theirs? I once lived in a condo that had a leaky roof over my apartment alone, and the remaining 20+ units kept voting against paying to fix it literally for years. That’s one building. You mtiply that by a.few hundred buildings on a given street, and absolutely nothing will get done, ever.