Relocated to Lamorinda two years ago with kids, happy to answer questions for anyone considering it
Seeing some posts from people researching this move and figured I'd offer what I know since we went through it pretty thoroughly before deciding.
Background: we were in Noe Valley, renting, two kids under six at the time. Did about eight months of research before pulling the trigger on Lafayette. We looked seriously at Orinda and Moraga too before narrowing down.
On the commute question, which comes up constantly. Lafayette BART to Embarcadero is roughly 45 minutes door to office if the timing works. In practice I'd say budget an hour each way when you factor in the walk to BART, waiting, and the other end. It's not nothing but it's also predictable in a way that driving never is. Orinda is one stop further east and honestly similar. Moraga has no BART which is a different calculation entirely, you're driving to a park and ride or driving the whole way.
On schools, the thing most people underestimate is how much the district boundary lines matter at the street level. Lamorinda overall has good schools but which district you're in affects both the school your kids attend This is one of those things where local knowledge from someone who actually knows the micro-geography matters a lot. We spent real time understanding this before buying and it changed which streets we were willing to consider.
On Lafayette vs Orinda vs Moraga specifically. Lafayette has a real downtown by suburban standards, walkable enough that you can get groceries and dinner without getting in a car, BART-adjacent, and feels more like a place than a suburb. Orinda is quieter, more spread out, beautiful if you want land or hills but less walkable. Moraga is the most family-suburban of the three, newer developments, younger families, but the commute tradeoff is real.
Two years in I don't second-guess it. The kids are thriving, we have space, and we still get into the city enough that it doesn't feel like we left entirely.
Happy to answer specifics if anyone has them.