Cards like Thrasios, Titan Hero, or Tynma the Weaver are generically good in nearly every deck just by themselves, so they see a lot of play to fill out the colors of a deck
The red package adds both control and reach
Boomerang Basics Boomerang Basics is a sorcery, sure, but 1-mana bounce effects are still somewhat playable, in the right decks
A Goblin Tribal Token deck full of creatures to swarm the battlefield under the command of Krenko, Mob Boss, who doubles the size of the army each turn
Flash is a great keyword, so why not give it to all your spells
This alone is not bad at all for MTG 's Commander format, be it casual or competitive, as Blue comes with a lot of good tools to counter opponents' spells, draw cards, and generally control the battlefield