Short answer: 4-3-3 is the most balanced. 5-3-2 is best if you want a $5 GOAT striker and ultra-budget defense.
Each formation has trade-offs. 4-3-3 (balanced) is the default. 4-4-2 (English classic) gives 2 striker slots. 3-5-2 (wingback) packs 5 midfielders. 4-2-3-1 (modern) packs 5 midfield slots. 5-3-2 (defensive) has 5 defenders — frees budget for one big-name striker. See full formations guide.