Are you able to pull your chairs out to sit on and still be on the rug? Can feel odd if the back half of the chairs is lower than the front. And yes tucked under the buffet will look ok.

why do you need to tuck the rug under the sideboard, it would be better not to and as mentioned above important that the chairs fit the rug when pulled out

How far will the sideboard be from the nearest chair when someone pulls it out to sit down? It looks a bit close in the mock up and that would be a bigger concern for me.

Thank you for your comments! So, I was looking at a 200cm x 300cm rug since it's a 6 seater table. However, the table is only 165cm long.

This should allow for the chairs to be pulled out and still be on the rug. The reason for having it under the sideboard a little is that the bottom of the rug would be in line with a doorway on the side wall so we'd want to keep that clear.

Good point about the top chair being close the sideboard. I might have to wait until the furniture is in situ then measure up for the rug to allow for all those things. We rarely use that top chair anyway but I will still need to open the doors!