What's the Best Blessing?

How do you wish someone well, truly from the heart? What do you say to them that you wish that no harm come to them, especially if they are really close to you? How to you express them that you truly wish the best, knowing quite well that often in life there are times when they might not quite get what they want. There are blessings that I have heard elders give to the young, traditional Indian ones, which if roughly translated mean "Be blessed and fructify, may you be bathed in milk!". Then there are exclamations like "May you live long!", "Wish you all the luck" or "God bless you". 

Question Question! Then, what is the best blessing? What would I want to really wish if I want to wish them the best? I have come to understand that wishing that nothing should go wrong is idealistic. While blessing, one cannot anticipate that things would go wrong too. How do I wish so that I remain true to it?
So a realistic blessing would be "I wish that God gives you the strength to overcome any setback." To learn to be a phoenix is a blessing. The best blessing that would work in dark times, provide strength when there is none. I have come to know in times when you really need some external motivation, counting such blessings helps you tide over.