Only place I've ever rented a boat is
Gig Harbor Boat Rentals. Nice boats for a good price. There are some great places to ride in Tacoma (Ruston Way and Pt Defiance being my two favorites). Overall it is fairly bike friendly, but most roads don't have bike lanes. Most drivers are good at sharing the road though.
Pt Defiance has some great dirt trails along the cliffs over the water and through an old growth forest that is great for walking. You're also about 50min from Mt Si which is a tough hike but well worth it, and about 75min from Mt Rainier which has hikes of all levels.