I just fly for leisure travel so I’m always paying out of pocket and looking for the most affordable F ticket. Usually just going PSC to LAX (or LAX area airports) with a connection in SEA or PDX and rarely found Alaska to have the cheapest F fares. Often they’re $100 to $200 more then Delta. Though I will note that this year if I look for travel in October on that route AS seems competitive, I usually book about 90 days before travel though so maybe F on AS jumps up faster then Delta. Either way, I do agree that getting lounge access with AS F is nice, and I really wish Delta did that, but I now hold the Amex Platinum card so lounge access isn’t an issue in SEA any more and isn’t an issue if I’m flying Delta.
I don't factor in the missed AS mileage because I don’t fly enough to really gain a huge amount of miles. I try to keep everything in AS mileage wise since I’ll do a few short hops between PSC and SEA/PDX every year but out of pocket is my main driver.