ouluck you seem to do a fair bit together.
The meals together I envy. Due to time constraints and commitments, we can't do that.
Though perhaps my idealised version of it, is not quite the reality for many and dinner is just a bicker-fest...
We're big on walking at Casa Wordfactory, and walk most Saturdays and Sundays. We've done that since they could toddle and will continue til they leave home. Luckily we have countryside on our doorstep. This usually becomes the time when we all talk and plan.
I also insist that at least once during the weekend we all watch one program or movie together. Yesterday we watched a recorded episode of Treasure Island with Eddie Izzard (very good btw).
DH usually carves out time to be with them on his own at weekends too. They always ask to play footie with him. Last weekend they helped him build a huge bonfire in the garden.
I don't think it actually matters what you do, as long as it's peaceful and enjoyable and that there's some form of shared experience to it.
Similarly I think every child needs regular one on one time with each parent. It doesn't have to be long or 'fun'. Just space to talk and share. On Saturday DH took DS to the hairdressers while I drove DD to a sports meet. What's important is that you are actually listening, I think, not distracted.
All I do is ensure that we have actually found these windows of time, especially when our life can be eaten by sports commitments, homework/revision, social engagements.