When you hatch a mystery egg, especially the golden ones, you may get a pink or black cottage, gold chicken and a gold gnome. The cottages are cute but you only need so many and will find yourself just selling them. It's not such a bad deal since the cottages are worth 3,000 coins each.
I noticed that every now and than when I opened an egg that sometimes my XP would go up 50 or 200. Tonight I decided to watch and discovered that when you hatch, usually a gold egg, and find a gold chicken or gold gnome you will also receive extra experience. The gold chicken you will earn 50xp and the gold gnome you will earn 200xp.
If you are using the
snagbar like myself you probably have already noticed that you only will get one gold gnome a day, but several gold chickens will make your xp go up just as quickly.
Remember though, the quicker you reach level 70, the quicker the game is basically over. You can always earn all of the ribbons and mastery's when growing crops but unless you have plenty of FV cash you will quickly become bored. After level 70 you do not earn anymore FV cash and 70 is the end of the line.
NOTE: Collectibles and quite a few other items found in golden eggs will up your XP as well.