It's all good
It's all BS
I don't know
There are superior systems than democracy
You'd have to make a good case to convince me of your first point. I think any time the government has the ability to choose who can vote, you know they're going to abuse that power.
As far as a foundational document, as you mentioned before, documents don't act as magical shields against government guns. Since presumable the government is responsible for deciding what the foundational document says, they can do what they want and claim it is legitimate.
But to get back to the original question, for any community larger than a small town, I would choose representative democracy over direct democracy.
My contention is that the flaws of democracy are ameliorated by limiting the functions over which the government may exercise authority. The less that is up for democratic rule, the better. Things like religion, speech, etc should be off limits to democratic rule.
In fact, the more I think about it, I find it hard to imagine any particular decision that is better made collectively by a majority rather than being made by individuals.
I am wholly against direct democracy because it is convoluted, costly, and highly prone to corruption. As a whole, I'm against democracy in general. As Winston Churchill stated, the greatest argument against democracy is a 5 minute conversation with your average voter.
Representative democracies have a better track record, specifically in populations of advanced society where people cannot keep up with the reality as it's laid out in front of them.
Long story short, stupid people should be limited in "rights".
Representative democracy is great because it allows specialists and experts determined by the people to make policies on which they are an expert. However, corruption and bribery is a serious problem in such cases.
Therefore, there should be procedures of direct democracy that allow the people to directly override actions seen as corrupt done by representatives.
That would be my preferred mix of types of government.
Also, we need to legalize recreational drugs and prostitution.