There seems to be no immediate plans to give us the first person back, so please give us the latest multiplayer version before the removal of the first person as a beta branch option! Unsupported as it is, it is a low-effort effective way of getting more people interested in the game and in getting the old people who left the game back into the game.
The game is already free, but you could even launch it as a paid DLC, to have the people who already paid for it pay for it again.