We have just bought a table that is 120cm x 90cm which can set 6 people but can only fit 4 chairs under it if you push them under. The table does however extend to 210cm so can seat up to 10 when fully extended. Maybe get one that seats fewer but extends?
I went for an extender, it was the smallest entender at Oak Furniture Land and extends at both ends. As is, it is a bit small for 6 but with one end extended it is fine, 2 ends open seats 8 comfortably. My problem is I 'needed' eight chairs and really the table can only have 6 around it and still look nice because I don't need the huge 8 seater table every day. My not perfect solution is to put a dining chair in each of the spare bedrooms
I love the flexibility of it extending at each end much more than the previous one that extended in the middle, that was a pain.