I live in in East Kent right now, and it's perfect for reserve, but the cost isn't worth it just for a few months on reserve. If I had the ability to (SO's job isn't as flexible), honestly I'd move to the Everett/Lake Stevens/Snohomish area or up to Bellingham. It's a bit of a drive, but there is a cheap shuttle bus from Bellingham right to the terminal at SeaTac (or jumpseat).
Everett (and surrounding area) is still mildly affordable, and it sounds like some trips may potentially start in Everett (I haven't heard for sure what the plan is on that). Just my .02.