Machoke can be obtained from Shining Revelry pack in the Shining Revelry set
Feather is incredibly tough to deal with, especially when cards like Boros Charm and Blacksmith's Skill start giving her indestructible and/or hexproof
The low returns on the cards should mean that scalpers will be less likely to try to buy the cards and re-sell them
Attacking is the easiest way to tap Sanwell, but you could also tap it to crew a vehicle and get the opportunity to play something on another players turn, as the ability ignores timing restrictions
There are very few cards in this game that can take more than one hit from a 6 attack Character, and none that can just shrug it off like it was nothing
You can use it offensively or defensively, which I firmly believe is a mistake in design, and noncreature spells are only getting more powerful over time