I don't think enough people talk about how lucky we are that the International Date Line can roughly follow a line of longitude 180 degrees from the Greenwich meridian. If you were on a planet with more land, or we could only draw it through the Atlantic or Australia, timezones would be a lot weirder.

It does split off part of Russia, I believe. The Florence meridian works slightly better for avoiding splitting any landmasses.

As I understand it, it's not the best location, it's just good enough and was very popular for historical reasons.

It's mostly a convenient location for a group based at the Royal Observatory, Greenwich to define...