Yes, driving across the bridges can be pretty killer, but it totally depends on the time of day. Seattle's done (and is doing) a lot of work on improving the flow of traffic throughout the city, but there's no doubt that the 520 is overloaded. The I-90 bridge is not as bad. I have a friend who commutes from Wallingford to Issaquah and braves the I-90 bridge every day.
Renting in Seattle can be seriously expensive, so you might have to downgrade your expectations, and I hope you're okay with a condo/townhouse.
And abaya and ktsptsp are up in Seattle. My SO and I have also been known to get up there every few months, especially since one of my SO's best friends moved up there last year.