This card currently has a market price of around $72, which, again, isn't cheap for a piece of cardboard, but for an SIR, is a pretty reasonable price
Earthcraft is the best source of mana to fuel a number of infinite combos involving Doubling Season, Cathars Crusade, The Meathook Massacre, and Corpse Knight, among others, but these cards only scratch the surface of your combo potential with this commander, so if thats your preferred style of play, the linked primer above is going to be your best starting point for deck construction
This step is crucial for preserving their condition, significantly impacting resale value
That's Honorable Passage in a nutshell: good for making Jackal Pup bite the hand that feeds it, not so good for stopping your opponent's Memory Jar deck
That second part wont matter much, since you either dont care that its a rogue, or you're copying a creature thats already a rogue