Sarkhan went back to Ravnica with the planeswalkers, helping the Gatewatch in the fight against Bolas
Yes, commander tax applies individually to partner with commanders
These are not considered significant defects and do not affect the grading, which can remain Near Mint (NM) .Deeper, larger, or multiple scratches, clearly visible and felt by touch, affect the cards appearance and reduce its condition, which should be considered Slightly Played (SP) or lower
That gets a pretty spot-on mirror in the card Sin, Unending Cataclysm
That means tighter quality control, faster turnaround, and a product made by people who care about the craft
*Ironic, considering modern day MTG explicitly has some jokey sets printed to be extremely powerful