The team seems to have a bird motif, similar to Team RWBY's fairytale motif and Team JNPR's cross-dressing mytho-historical figures motif. Each member's name is synonymous with or similar to the name of a bird.
Furthermore, the birds lend credence to the possibility this group shares a heraldic motif. While the cardinal is an obvious allusion to the religious station of the same name, the others (Thrush, Lark, Dove) are figures which were typically used on heraldic shields.
As revealed during "Forever Fall," each member of the team has eyes which are a shade of blue.