Each day a new free design is set up in each section...alphabets, red work. etc. and the designs are selected by the one that has the greatest number of votes, but not all designs are available to be voted on/going to be available for free. Some designs are for purchase only. You can tell by looking at the designs, if there is a place to vote, then it is available for free.
Letvia is keeping track of voting requests and lets us know what design is wanted. Post a request for the letters. I think you are just one of many who would like to restart the sakura font when the sunflower font is through. * 4 u :)