I'm delighted that for 25 hours each week, I'm unable to check my e-mail, be in touch with clients, work on pressing deadlines, or be connected to my phone, or watch TV and movies.
Instead, I spend quality time with my wife, children, and friends. I read. I play board games. I enjoy long, extended meals with equally extended discussions.
Can you do this without the restrictions of the Sabbath? Of course. Is this the only way to have quality time with friends and family? Of course not. Does it involve trade-offs, such as not being able to hike around in nature on weekends (which is arguably part of how we would want to rest and relax)? Yes, for sure. Everyone finds their own way to observe.
But in my experience, the traditional set of trade-offs is very much worthwhile. I work nonstop during the week, and while I love my work, it's fantastic to take a break, think about what's really important in life, and even catch up on sleep -- which is, let's be honest, another nice part of the Sabbath!
I should add that observing the Sabbath as an individual is almost certainly a ticket to loneliness and/or misery. It only works if you do it within a context of others -- family, and even more importantly, a community -- who are similarly inclined. I have, over the years, spent a handful of Sabbaths completely on my own, and those were freeing and meditative in their own ways. But I've long argued that a very large part of Judaism's success is that it forced the creation of close-knit communities. The Sabbath is one factor that leads to such communities, and it's then that the community gives back.