I LIKE open plan but I don't LOVE it.
When we first moved in, DH was all on to knock every wall downstairs, including the hall, to make it entirely open plan. We decided to not do that. Downstairs was a hall (stairs straight up through it), sitting room to the left as you walked in, and kitchen/diner across the back of an ordinary 3 bed semi.
About 5 years after we moved in, we extended out the back across the entire width of the house. Kitchen and dining stayed roughly where they were (but both improved), but we put on the "playroom" going out into the garden and a downstairs bathroom with shower and a utility cupboard holding the washing machine/dryer/ironing board etc.
The "playroom" is in effect a second lounge. There is a tv there, and we have 2 decent chairs and a 3rd that DD uses, when we are all out there watching something. There is a big open space to do yoga on the floor. The dresser moved there (under tv) from the dining room holding the "good" crockery etc. DD has a study desk there.
We do a lot of living in the playroom, all together when we get home and cooking is going on while schoolbags get emptied/homework started and someone is on the computer at the kitchen table etc. We often sit there together in the evenings after dinner.
But we also really like having the original sitting room, that we can close the doors on, has a wood burning stove, and feels more cosy at times (smaller space, lower ceiling, darker walls, less light from windows, north rather than full south facing etc). DD likes to retreat there a lot (ASD). The Xbox is on that tv, and that is the large tv. The 3 piece suite, so room to lounge, is in there. The firelight (and candlelight) in winter does make it cosy.
We had changed the doors between the 2 rooms originally to have some glass in them, and more recently changed again to have large glass panels in them, and into the hall. So neither room is cut off from the rest of the house entirely, but being able to close out the smells of the kitchen, or the noise from someone clattering up and down stairs, or to let someone have some peace and quiet alone, is useful for us.