I would go for that. The aisle in the back is not good but it's not unbearable for a 2hr 30min flight. I would not upgrade on the DEN-SEA flight because for me, it's only a 2hr flight. I would be upset if I were in F for the domestic short flight and end up in Y on the long trans-pac flight. You have a good chance at getting the upgrade (UDU) anyways for that flight. Good luck on your choice. I would leave earlier and spend time in the RCC (not really that impressive, but hey most aren't in the US)

PS. I can't believe I missed the 1K lol sorry