When organising private games with no open seats it would be nice if there were empty boxes on the dashboard indicating how many more players need to be invited to fill up the game to tell if any players decline the invitation at a glance.

It could look something like this: http://prnt.sc/c21272 - A five Player game with white squares representing how many players need to be added.

Well what I normally do is count it manually.

A good idea is to be aware of the number of players. For example, this is how it looks when the game has 40 players:



The first row goes to 21, the second goes to 19, for whatever reason. Would be easier to count if it was 20-20. But it's a good hint; base your counting around that.

Use open seats with inpossible prereq, as a workaround

I think what he wants from this is not to know the max players but to know about any declines in the game.