Enjoying the game and benefitting the guild could go hand in hand. I would like to propose weekly contests to challenge members in various phases of the game and create a little competition within the guild.
Here's the way it would work. Three days before the contest would start a mass message would be sent indicating the rules of the game and the exact time the contest would start and finish and the REWARD. The contest administrator would create a snapshot of the guild. At the conclusion of the contest another mass message would be sent letting all members know the winner for the week. Additionally a new rank might be nice "Weekly Winner" or something like that.
Example: For the week of July 13th - July 20th, Level lord. The guild member that achieves the most levels between July 13th starting at server time 7:00 and finishing on July 20th at server time 7:00. At the conclusion of the contest, the winner will recieve 50,000 gold and be assigned the rank "Weekly Winner". The only rule is no funny business like trying to delevel your guildmates ;D Have fun and good luck.
Example: For the week of July 20th - July 27th, Kontribution King. The guild member that makes the most contributions between July 20th starting at server time 7:00 and finishing on July 27th at server time 7:00. The contributions will be divided by the ending level so all members have an equal chance to win. At the conclusion of the contest, the winner will recieve 1 FSP and be assigned the rank of "Weekly Winner". Good luck and happy hunting.