Have you looked around the board?
Taxi will be one of the more expensive options. Ship's transfers will get you there in plenty of time for a 12:30 flight. There are many private transfer options mentioned here, like the wonderful Rome in Limo.
8am is actually a bit late for most cruise lines to arrive...most are docked before 7am.
They do it on all the HAL ships, if possible and not unsafe due to weather or similar. On some other cruise lines, the bow is not set up for pax to be out there.
The itinerary is important.
The airfare is the airfare. Being American doesn't affect that AFAIK.
Some reading on the Alaska board would be beneficial. Sailing from Vancouver gives you the more scenic true Inside Passage, and usually more time in ports.
You base this on what...the website? You know the website only tells you unassigned cabins, because you can't see GTY bookings? Literally, one additional booking can close out at least one (and possibly more) cabin categories, depending on the type and number of GTY bookings.
Yes, but we have sailed 5 times since resumption...2022, 2023 (3x) and 2024, and never put in a picture. Never did Verifly. Just showed up at the pier with required negative tests, and boarded quickly. I assume part of the reason for pretty normal speed boarding was (a) Neptune Suite pax and (b) low pax counts in 2022 and 2023.
Sounds reasonable. You can look up current and forecasted Vancouver weather, and perhaps San Francisco and LA, and subtract 10 degrees for being off shore.
Doing some reading will in fact benefit you, as your questions are extremely general. This sort of question is asked frequently...there are many threads on the topic. In fact there is a "which cruise line" thread just two below this one as I write this.