I see that currently you receive 600 gold and 25 credits if you succesfully invite anyone to play. That is not alot, really, considering that with each invite do you bring in wholly new players... If there are to be more members playing Algadon, offering a larger reward might get more people interested, resulting in more players.
Ofcourse, it might be possible to abuse it, but that is not my area, i just think a larger reward for helping recruit to the game would benefit all.