You may be able to seat less at a tulip table and if you can live with that go for it. It would look great with your striped rug. Clear acrylic chairs would look good such as the IKEA Tobias but I would go for white solid or a mix of grey, white and black.

I have to agree that with young kids an informal area for eating, craft, games is great. What benefits are you aiming to achieve in pulling out the wall? (The noise barrier between kitchen and living can sometimes be a plus!). If you do go for the open plan option, would a table height section of the island bench work for your space? [https://www.houzz.com.au/photos/clontarf-modern-kitchen-contemporary-kitchen-sydney-phvw-vp~6297803[(https://www.houzz.com.au/photos/clontarf-modern-kitchen-contemporary-kitchen-sydney-phvw-vp~6297803) Or a kitchen breakfast nook that would also include storage? However, this option might not grow so well with your family (a lot of people consider bench seating to be uncomfortable for adults).... [https://www.houzz.com.au/photos/putney-loft-conversion-contemporary-dining-room-london-phvw-vp~6690827[(https://www.houzz.com.au/photos/putney-loft-conversion-contemporary-dining-room-london-phvw-vp~6690827) [https://www.houzz.com.au/photos/two-time-award-winning-kitchen-traditional-kitchen-chicago-phvw-vp~105687[(https://www.houzz.com.au/photos/two-time-award-winning-kitchen-traditional-kitchen-chicago-phvw-vp~105687) I think as long as it isn't two (or 3?) identical sized tables lined up parallel to one another then it would be ok and not look cafeteria-like. Also when we were choosing island bench stools I took my youngest (nearly 3 at the time) shopping and had her try out all the stools first. We found sturdy ones that are easily wiped and she could get on/off by herself. Her mocka highchair/junior chair also works well.

You can choose chairs either to match the curve of the table or the diagonal, chunkiness of the legs. Though that timber is going to be difficult to match. I'd go metal. You can contrast it with slim legs or go with the chunkiness .

All looks good except I would like to see the opening between the family and dining opened all the way wall to wall and either move the Fridge or Pantry to the other side of the kitchen. This will make the space look more open and feel bigger and allows for the dining table to be extended by just rotating cheers