Ready to harvest?

Yes.

I harvest based on if the strain is Indica, Sativa, or a Balanced hybrid. When the bulbous heads of the trichomes are fully developed but still translucent, plants will produce a "high" and stimulanting effect, less sedative. It is the perfect moment to harvest strong Indica strains. When these bulbous heads turn milky is probably the best moment to harvest most available hybrids. When 70% of these trichome heads are milky and 30% amber, it is the perfect time to harvest mostly Sativa hybrids and long flowering strains (like Haze).

Should be fine. still lots of THC in all the trichomes.

In principle yes, but I would wait until 90% of the trichomes are milky, then the THC level will be maximum. But if you want a more sedative effect, then you can wait until most of the trichomes become amber, this means that the THC has broken down into simpler cannabinoids.

It probably could go another week just to get a few more Amber but it's a personal preference. I go for an average mix of 33% Amber. 33% clear.33% milky or a close too.