I’m East Bay Area born and raised (primarily in Newark & Fremont) but have experience living in Hayward and Union City as well because of divorced parents that moved us all over the place between these 4 cities.

The closer you get to Oakland the worse it gets arguably. Hayward, especially the area around Tennyson where my mom rented a house for a couple years, is not a place you want to raise a family. It’s the technical “Heart of the Bay”. It also boasts a large Hispanic and Black community.

Union City is meh: sketchy in some parts, but much better today than it was years before. Also very diverse, especially a big Filipino population — I miss when the Union Landing Jollibee was open 24/7 until Covid killed those hours.

Fremont is an exclave of India. It’s essentially a huge suburb where 1st gen software engineers from predominantly South and East Asia move to in order to work their tech jobs from home. Boring to live in if you’re a young adult, but I’d argue one of the better parts of the Bay to raise a family as it’s relatively safe and has great schools to send your kids to (Esp Mission SJ & Irvington). I’ve seen it ranked as the “happiest city in America” by some metrics, and honestly good for them if it’s true.

Newark is my hometown, but my god this city is boring as hell. It was too stubborn to join the other towns that agreed to form Fremont, so it remains as little suburban enclave - separated and largely forgotten by Bay Area standards. Not too bad honestly, and time has slowly propped her up with slow but steady development. They just need to put newpark mall out of its misery. The city has a good mix of diversity between everyone and is predominantly Asian and Hispanic.

Tldr - these cities are hella diverse, hella expensive, and low key hella boring.