The final reward ended up being fairly lame: a "Legendary Supporter" resource card, and extra copies of the Distinguished Service Pack and K-Pack. Supporters of all levels get these already, so the only way to "get rid of them" will be to sell/give them to people who buy the game in 2013 because they didn't get in on Kickstarter.
We worked on a lot of ideas for that final reward. The pressure was on, and topping the other gifts was really hard. A few days ago, we had what we thought was the greatest idea ever, and just before we could announce it, the deal fell through. (Don't worry, though, the idea is not lost as we are already planning next year's rewards, so we won't be caught off-guard again).
The problem is that we can't afford to spend weeks to find the perfect reward that will please everyone, as we are busy putting the finishing touches on the game and its expansions (we have added a token sheet for the base game, some optional rules here and there, and we are tweaking various aspects of the production, like the "recipes" for the speckled dice).
I find it interesting that they are planning additional rewards for next year, even though this was supposed to be the last one. Some people were asking for an organizer tray, others were asking for card sleeves, and I still think they should be doing more speckled dice to complete the set. Maybe we'll get all of these things?