I'm a huge roundabout fan, but this does indeed look nasty. Seattle area driving in general is pretty bad. There's an exit on the 5 in downtown Seattle that's on the far left lane (Seneca street I believe) that feels like putting your life on the line every time you need to take it.

There are multiple left lane exits (and onramps!) on I5 in downtown Seattle. Fun times.

Bonus points if you’ve found all the express lane on ramps.