Short answer: Balance: one marquee ($4-$5) + 3-4 cheap quality picks ($1-$2) + 1-2 mid-tier ($2-$3).
Winning squads on TenDollarPick (based on community voting) follow a pattern: 1 superstar to attract attention + budget players in key roles (especially cheap goalkeepers like Pickford or Pope at $1) + 1-2 mid-tier all-rounders ($2-$3) to glue the team together. Pure-budget squads lose to flashy ones. Pure-flashy squads lose to balanced ones.