My kids are off at college now but we lived in a few different areas, all with good mountain biking, while they were younger.
We started in Tucson, AZ. There is truly great mountain biking in the mountains surrounding the city but you mostly have to drive to trailheads. I lived close enough to Catalina Hwy. to ride up to Milagrosa Ridge from home when I was in really good condition but otherwise had to drive 30-45 minutes for most rides. Good public schools at the time were limited to the foothills to the North. Hot, but not as hot as Phoenix and housing was very affordable. We paid $153K for our 4br house with a pool on an acre in '97.
From there, we ended up in El Dorado Hills, CA from '02-'07. Terrific mountain biking near there as well, but again, you have to drive your bike around to get to the good stuff. Pretty hot summers there too. Schools were good, houses cheap compared to the Bay Area but not by most other standards. We made some good friends there but there is a lot of ultra-competitive mom stuff going on at the schools. It was at times both hilarious and annoying. People there seemed to want you to know they had money, whether they actually did or not.
Next up was Redmond, WA from '07-'09. The weather up there doesn't bother me and dense forest trails are my favorite. Good schools according to standardized test scores but we weren't thrilled with them. The way they taught math drove me bonkers. Driving is a huge PITA up there. Redmond doesn't look too far from Tokul or Duthie on a map but it can take an hour at times. Public transit is great with express buses every 8 minutes if you're going between Seattle and the Redmond but not so good from Redmond to Issaquah.
From there, we moved to the Monterey, CA area. My office was in a business park immediately adjacent to Ft. Ord/Laguna Seca Raceway so I had all of the Sea Otter trails to ride after work or at lunch. It's lacking tech but the access was great. From my house in Carmel, I could also ride into the not so well known trails in Pebble Beach. The trails there are short but steep. Real estate there is insane. I was lucky to rent from a family who had owned the property since 1904 and hadn't raised the rent in a decade of more. We were 3 blocks from the water and it was awesome.
We finally ended up about 45 minutes up the road from Carmel in Scotts Valley. We're about 5 miles from Santa Cruz, which is close enough for convenience but far enough that we don't have their issues with homelessness and property crime. Cycling is huge here. Kids ride their bikes to school and all over town after school. The pumptrack and skate park are packed all afternoon. I have no driving access (2 miles of pavement to the main trailhead) to what I consider to be some of the best trails I've ever ridden. I walk 2 minutes to the dentist, 5 minutes to the doctor. I walk home from the mechanic if I need to drop the car off. Tech salaries here are quite a bit higher than elsewhere and while it's not enough higher to compensate for housing prices in towns like Sunnyvale, Mountain View, or Cupertino, it's more than enough to make the difference in Scotts Valley. I manage a team of 74 engineers from entry level through the Principal/Director level at a big semiconductor company so I know this intimately. If it's not already obvious, I really like it here. We're slowly looking into other areas with riding from the door for retirement but will likely keep this house as a rental/Airbnb even if we do move.