Renaissance Venice
was one of the longest-lasting governments with a substantial democratic component ever.
It ran for over 500 years under range voting
using a 3-point scale;
plus several additional centuries under previous forms of
semi-democratic rule.
This longetivity was despite what would seem to be large inherent disadvantages
and dangers.
Venice began as a Greek-style democracy and gradually changed character to end
as an aristocracy (i.e. only a democracy for the
few thousand richest families).
Even at the end, though,
theoretically the "assembly of the people" always had the right to reject the aristocracy's
range-voting-based choice of the Doge. In one view this veto right, since apparently never
exercised, was a mere "formality" and not genuine power;
in another view it was genuine and the exercise of
democratic power was via
the threat of the veto. (In the famous words of chess grandmaster Aron Nimzowitsch,
"the threat is stronger than its execution" and I think this chess maxim often applies
to governments even better than to chess.)
Venice also gradually evolved with time to diminish the power of the One Doge
versus the Many in the Grand Council. The principle of "checks and balances" was well
appreciated in the design of Venice's government.
At its peak Venice was the highest-trading city in the world
and one of the greatest (if not the greatest) naval powers in Europe.
Although certainly not perfect,
historians have admired it as the greatest success (in terms of justice, happiness,
technology, prosperity, art, etc) in Europe during that era.