That's a solution, except even with a rectangular table, the most important person sits against the longest side and the subordinate person sits at the shorter side. Thus head (and foot) have no meaning.

It gets even worse with certain Chinese ways of seating at banquets. You have a square table with one side facing the company who are seated at other tables below. The host and guest of honour sit at either end of the table-- the head and foot, if it were rectangular-- except that they sit /sideways/ to the table, facing out to the company. Try describing that without tears.