Not only does this mean the number of times you can activate the abilities are limited (by my count, Esper Dragons, the tier one deck that runs the most spells in standard, plays 25 instants/sorceries), but also that Disciple of the Ring is directly competing for the same resource as extremely powerful delve cards like Tasigur, the Golden Fang and Dig Through Time and also a nonbo with the new spell mastery mechanic
"Is the MTG Arena Mastery Pass worth it?"
That card is horrible in this deck, by the way, so there's your first upgrade - literally any other removal spell
Each booster box contains 24 packs (12 cards per pack)
It is quite easy to control how much this shoots for
Take Controvert: A full-range counterspell sure is nice, but at 4 mana it's prohibitively expensive