Would this be a good location for families looking to relax on a weekday afternoon?

Definitely

Great place to relax and enjoy with friends and family

It is very scenic. The vineyard is open Wednesday through Sunday and closed Monday and Tuesday. Hours can vary from week to week and early closings are possible. You can bring your own food, or on Saturday and Sundays they sometimes have a visiting food truck which differs from day to day. Outside beverages are not permitted. There are chairs, benches, and picnic tables outdoors, and dining tables and chairs indoors. The building is a repurposed airplane hangar and so is very spacious. There is a balcony. Some Saturdays and Sundays they have live music that may be indoors or outdoors depending on the season and weather that day. Children are allowed in the company of a parent or legal guardian. Schedule of business hours, music, and food trucks is posted on their website.