For one, it needs to be available, and not just on the secondary market
The Deck Tune feature is especially useful if you already have a deck built and want to improve it without completely changing the strategy or replacing half the cards
An altered Magic card is still legal if the original text denoting the name of the card is unobscured, and the paint isnt too thick to alter the thickness in shufflingthough this is ultimately to a judges discretion, and they can refuse altered cards entirely
Job select cards are generally pretty solid, though there are a couple of stinkers (i.e., Red Mage's Rapier and Sage's Nouliths)
Be they whispered tales of powerful cards, such as Dark Confidant and Life From the Loam, or literal legends, in the form of the named creatures that head up each Guild, the streets of this colorful city are soaked in 16 years worth of myth-making
I want to be able to use my experience playing Magic over the years to continue to tune, work on, and personalize my decks over time