hard to beat the WT for easy logistics. Consider the Boundary Trail in the Pasayten as a more isolated alternative. Some good loops in the Glacier Peak wilderness that mostly involve the PCT, so I'm not sure if you want to do a repeat. Planning a climb of Glacier Peak would also be on my list.
If you want to do a couple smaller trips, consider heading up HW 542 and checking out Copper Ridge, High Divide, and environs. Lots of great subalpine terrain up that way.
The Olympics have a bunch of great options for big loops. I'm not as fond of the area because of permit hassles, but most Seattle folks disagree. There are also the olympic coastal trails, if you are into beach walking.
You can attempt to squeeze some info out of nwhikers.net, but I think it would be more appropriately named nwtrolling.net/bickering haha