It's hard to think of a place that would be fine
While we already saw the power of Thalia in powered formats, where she can hate out combo decks and slow down sweepers, such as in the Five-Color Humans deck above, the card has also enjoyed a great deal of success as just a good card for aggressive, creature-heavy decks. Creatures (27) 3 Fiend Hunter 4 Champion of the Parish 3 Avacyn's Pilgrim 3 Mayor of Avabruck 3 Thalia, Guardian of Thraben 2 Restoration Angel 3 Sigarda, Host of Herons 4 Silverblade Paladin 2 Druid's Familiar Lands (25) Spells (8) While Thalias ability is so good, she would likely see a fair bit of play even without first strike, its actually the first strike that really gets her over the finish line
Cheap, aggressive creatures, with Lightning Bolts and Chain Lightnings helping clear the way
The packaging was just as exciting and Disneyesque as it looked online
Pair it with cards like Cathars' Crusade, and those small creatures turn into game-ending pressure before opponents have time to stabilize