There are no goals for stats, no set amounts to aim for, no combinations of stat distributions that are good. It is a very common misconception to focus on stats, or aim for the 'right' ones. They do not exist. The only stat that will always be correct to pick is Intellect. Haste increases the healing of all your HoTs linearly, which means there are no, and cannot be, any breakpoints. You will have a 10% reduction of Haste rating effectiveness after acquiring 990 Haste rating, which will make it slightly weaker overall. At your discretion, you can start gearing for other stats at that point. After 1320 Haste rating you will have 20% reduction, at which point you might want to look into getting other stats instead. Keep in mind, that diminishing returns only work for Haste rating, not for effects that give you Haste percent increases like Bloodlust, Heroism or Kindred Affinity bond.