There are plenty of commanders with a tap ability that could really use haste, and its also terrific with the sorts of commanders that need to attack in order to trigger some nifty bonus
players should always reroll 500 Gold quests, as there's a chance they'll turn into one that offers more
Value supports grading for clean copies
The drawback of giving your opponent a 3/3 flier probably matters in Constructed formats, but its less of a problem in Commander (see: Swan Song)
If a creature with one or more +1/+1 counters on it gets enough -1/-1 counters put on it to cause it to die, it leaves the battlefield with all those counters on it
At four mana, he can sit at the top of your mana curve, and if you manage to drop a haste enabler such as Goblin Warchief, you can start doubling your goblins straight away (which then also have haste to attack the turn they enter)