From Antique shops, Restaurants, Wineries and Breweries Downtown Snohomish is definitely a must see.
Take a ferry from Mukilteo (23 mintues away from Lake Stevens) by car or by foot to Whidbey Island. Start off in the small town of Langley which is located right off the water for shops and a bite to eat. Then head over to Coupeville (Ridel's and I's favorite spot). The Coupeville Wharf is a must see and great to walk along the pier and take photos. A big MUST is getting ice cream at Kawpaw's Iskreme, I am not kidding you when I say Ridel went back not once but THREE times in one day to get different flavors. They have the best homemade waffle cones and very large portions (you'll be thinking to yourself....how did Ridel eat so much?). Coupeville also has fun little shops along the strip that you can walk around and see as well. Lastly, Ebey's Landing is beautiful. There are hiking options there or just sit on the beach and look at the ocean.
Thursdays, 3pm to 7pm; located at the intersection of Cedar Ave. and Pearl St
Wallace Falls offers 12 miles of glorious foot trails, don't worry you don't have to do the full 12 miles. You'll be able to see powerful Wallace Falls, with its three tiers of water rushing over rock and timber. Along the way, climb the trail to the lower, middle and upper viewpoints, and watch the waterfall tumble into the clear pools below. Just a heads up, parking is limited and you will need to pay for a day pass (reasonable and worth it).
Take a ferry from Mukilteo to Vancouver roughly a 4 hour ferry to see some great sight seeing options. We highly recommend Stanley Park