My first take at dynamic blocks. Hope you like it!
Table contains settings that allow it to change between number of chairs and their position.
Standard width for dinning area of a table is 62.5x40 cm, so you can use this as a guide for streching.
Table is streched 15 cm on the left and right, when you add chairs to these positions.
Chairs are standard 45x50 cm and you can change their shape inside block editor, because this is a nested block.
Block also switches between chair and bench, for additional flexibility.