Citizens United wasn’t legislation, it was a Supreme Court decision. The only way to fix it following the current rules is to ask the court again or to change the Constitution. Of course, if you are willing to just ignore laws then you have many options (see current Presidential administration for examples).

I am quite sure. I was out with a friend and he got fined for not carrying ID. The legal requirement starts at 16.

Both true and not true.

The idea that you have to register to vote is not normal in most democracies.

For example, in the Netherlands you have to carry ID at all times, whether you are voting or just going for a walk. You don’t have to register to vote, you just get mail a while before the election with a paper that you take to the voting booth, which is usually a few minutes walk away.

Such a system prevents fraud (which is already a non-issue in the USA, even with its confusing and difficult system), and also makes it easy for as many people to vote.

The goal of voter ID laws is to provide ways to disenfranchise people, by making things slightly harder and create plausible points to not count some ballots.