Thanks Bayohne. Good news! And something that should help both sides.
To those that feel failing them isn't right or fair, to let you know, I have friends on my server who are still desperately trying to complete their Harlequin Armor Set (requiring Faction Credits, which you get from completing leves).
So they aren't failing their Guildleves, and they are choosing to complete them to gain more Faction Credits, faster, to try and get those rare items from Faction Guildleves.
I think that once SE adds more unique, rare Items as rewards from Faction Guildleves (or make Guild Marks more valuable (add new items that are worth buying from each Guild for Guild Marks) and have increased Guild Mark Rewards from Faction Leves), these would incentivize more Players to consider completing Guildleves.
I also like Alexia's idea of having stuff like rewarding Anima or Guardian's Favor, or other interesting additions (besides Gil).
Ultimately, though, it's up to the individual Player how they want to play. As long as it doesn't hurt you, it's their choice. More interesting, rare items would help as well, like if they had made Tattered Robe (for Vintage Robe) only available from a Faction Guildleve, or, say, you can only get Dragonscales for a new Dragon Bow, from a Faction Guildleve (all for Faction Credits)), and suddenly, there's a lot more incentive to complete Guildleves.
I think we'll see it balance out by itself with better rewards as Bayohne / SE is saying, whether it be from immediate completion (the new "Bonus" they're talking about), or indirectly with awesome Rewards / Items from Faction Guildleves and Guild Marks (which would require Guildleves to be completed to gain Faction Credits or Guild Marks)).