In addition to the usual Spring Festival items, you can get some other useful items. Anfalas Star-lit Crystals cost 60 Spring Leaves and are Bind on Acquire, so they must be bartered by the character that will use them. Essence Reclamation Scrolls cost 90 Spring Leaves and are not bound, so can be sold, passed or traded, e.g., by a lower level character.
The scheme for festival dyes started with last year's Spring Festival continues. These are the new dye colours that cannot be crafted and are only available for festival token barter or Mithril Coin purchase during festivals. Each festival has 2 colours for festival barter and 2 colours for MC. The next year, the festival barter colours are available for MC and vice versa. The market for the dyes is thin and hard to predict, and some colours are more popular than others, but I have sold hundreds of various colours for 5-10g each over the year since they introduced them.
For the Spring Festival, you can barter 15 Spring Leaves for either 6 Lavender Dyes or 6 Dark Purple Dyes. You can pay 10 Mithril Coins for either 6 Shire-Plum Dyes or 6 Bullroarer's Green Dyes.
As usual, I recommend the Ale Association and Inn League delivery quests as a way to generate festival barter tokens. If you do all 11 deliveries for both factions, you can earn 66 Spring Leaves in a well-planned hour. See my blog post for details:
http://shadowbanekin.guildlaunch.com/users/blog/2962374/752821/the-ale-association-inn-league-delivery-quests