Im going to Granite Peak in 2 weeks 3 hours each way. But for you DH or Cascade is a great ride. It's all commercialized populated cities. Lots of restaurants, stops, and shopping if you need to break up the trip.
If you did a Saturday leave 6:30 am and stayed and rode till 8 ish you'd be home before midnight. You wouldn't regret the trip. Both are a bit bigger with longer runs. DH has a nice MELLOW 1 mile run. It was a great break to just chill and monkey around down the mountain with my kids.
Cascade can get real crowded with kids under 12, they ride free. Great for families but as stated if your looking for a little less crowded with "kids" DH either way you can't go wrong.