Go to your local nursery and see what they sell. Most will offer smaller label (not Scott's or Pennington) grass seed blends formulated specifically for PNW lawns. It doesn't really matter what the specific mixture is....you pick more for usage than by seed type - high traffic or sports blends, shade blends, premium blends, all purpose blends, etc.

My local nursery here in Kitsap sells an overseed mix, which is really an all purpose blend. Works well for most applications with the exception of lots of shade. No turf grass works all that well under those conditions :-)

I'd just check to confirm that whatever blend you choose omits Kentucky blue grass (doesn't do well in western WA) and limits or excludes bentgrass, as that can be a detriment to a good looking lawn.

Thank you gardengal, most helpful.