I thought I would start out with Big Break in Oakley. I enjoy kayaking at Big Break because it is relatively peaceful and there are few motor boats due to the depth. It appears to be a great place to fish for bass as I've seen others catch lots of fish but I haven't caught anything yet. There are a ton of birds to view such as Pelicans, Sand Hill Cranes, Herons and Egrets and lots of ducks. According to the East Bay Regional Parks District web site: "Big Break was once an upland farm, now submerged. It is a small bay or estuary at the edge of the San Joaquin River, and lies in the zone where salty seawater meets snowmelt and runoff from the Sierra Nevada mountains. The mixing of salty and fresh water produces an “edge effect” for increased habitat and species diversity. It makes Big Break a fine home or stopover spot for a wide variety of species, particularly birds and fish."
The park itself is very nice. There is free parking and restrooms available in the parking lot and near the launch site. The only downside to Big Break is the 1/4 mile walk from the parking lot to the launch site. It's paved but you definitely need a cart. If you want to avoid the hike then you can put in at Big Break Marina but they charge $10 to launch your kayak.
Once on the water you can head northeast toward the San Joaquin river or head west toward Dutch Slough and Bethel Island. The NOAA chart for this area is 18661.