I live on the southern edge of Santa Monica. My parents have started staying in the Marina when they visit as it provides easy access to things (which for them are LAX, meals, and us) and it is a bit cheaper than Santa Monica. They have been staying with the Pacifica Hotels who have 4 properties in the Marina (switching between Hotel Marina Del Rey and The Kinney depending on rates).

Since you now have Uber/Lyft, bikeshare, plus public transit I think it is fine to base there for a few days. Easy enough to get to Venice or really anywhere on the west side if you want. Plus you will be close to the fireworks! You could also come up to Main St. Santa Monica for our 4th of July parade!