A discard outlet that costs five mana when your curve ends at five will not greatly enable any graveyard synergies you might have in an appropriate time scale
Vigilance and goad can create a strong deterrent, so think about cards like Disrupt Decorum also
Compared to the current standard meta of Guilds of Ravnica, those were weak for competitive play
Putting mana rocks in your deck isnt difficult, though, and thats before we talk about things like Basalt Monolith
We know there will be a mix of old cards with new art and new cards also present in the Final Fantasy bundles and boosters
As an example, Emchompite says that cards that were included within Japanese sets, like the Secret Rare Yveltal EX from Best of XY, but as promos in English, are usually more expensive in Japanese just due to the nature of their release (i.e., having to pull the card from a pack vs a guaranteed promo card in a product)