As a Seattle resident I love Alaska Airlines (MVP/MVPGold typically on it every year) and its always my first choice if options are comparable, but with Delta growing here, more and more I've been booking with Delta since they tend to be undercutting the price often.

However, the biggest issue is that Alaska (and Southwest) have very generous change/cancel and same-day change policies, even for non-status members.

Having such a generous change/cancel policy is extremely important, and unless Delta starts charging less than $200/$75 for far-out-changes/same-day-changes, I can't really fully use them.