Thats a good example of wanting immersion at the gameplay level, and how the best intentions could crash and burn
Each Booster Pack contains: 15 Mystery Booster 2 cards 10 Commons or uncommons 2 Cards of each color 1 Multicolor, artifact, or common or uncommon land 1 Rare or mythic rare 1 Future Sight frame card There is a 60% chance for a rare or mythic rare
I dont think a Detective-based deck may become super competitive in particular considering the amount of very effective cards that will be released in Whispers in the Well but we recently saw a Pirate Action deck worth less than 70 topping a Set Championship thus there is no reason a deck based on On the Case Starter Deck cannot be enjoyable also in a competitive setting
Either way, with the rest of the board empty, Isabela can be an absolute monster
The D23 Disney Lorcana panel featured Ryan Miller (Senior Brand Manager), Brent Strong (Imagineering Creative Director), Steve Warner (Game Designer), Shane Hartley (Creative Director of Global Games) and Richelle Brady (Community and Engagement)
Ruby/Sapphire decks normally have a good amount of removal (outright banishing characters) and ramp (adding extra ink in a turn)