1. There's nothing preventing the formation of more political parties - it's just that they garner little support. Just look at the Libertarian and Green parties.
Thats because voters dont want to vote truthfully as it may cause their next choice (one of the major ones) to lose. Hence, we need instant run off voting, or AV.
2. However, the more parties with elected officials the more likely partisan politics will be a greater problem. In other words, the more disagreements in Congress and the more gridlock we will get.
If anything, there will be far less partisanship if a sizeable minority centrist party can be established.
3. Polls are open from 7am to 7pm where I live. No need for another national holiday.
There are plenty of the working class that have incredibly random shift patterns. There needs to be a national holiday.