While you could just put both on the same target to give it an extra +1/+1 counter, the better play is to put each backup on a different creature and focus on sharing the abilities out instead
Just tap them for mana, play your bounce spell, replay them, and tap them again
Path of Discovery has a lot of cool synergies even beyond this in Commander, hence why its high up on this list
Archelos, Lagoon Mystic Brokkos, Apex of Forever Brokkos, Apex of Forever Damia, Sage of Stone Felix Five-Boots Glarb, Calamity's Augur Gonti, Canny Acquisitor Henry Wu, InGen Geneticist Indominus Rex, Alpha Kadena, Slinking Sorcerer Kotis, Sibsig Champion Kotis, the Fangkeeper Leovold, Emissary of Trest Maralen, Fae Ascendant Mimeoplasm, Revered One Muldrotha, the Gravetide Muldrotha, the Gravetide Nashi, Moon's Legacy Nine-Fingers Keene Otrimi, the Ever-Playful Rayami, First of the Fallen Sidisi, Brood Tyrant Sin, Spira's Punishment Teval, Arbiter of Virtue Teval, the Balanced Scale The Master, Transcendent The Mimeoplasm The Wise Mothman Volrath, the Shapestealer Vorosh, the Hunter Xavier Sal, Infested Captain Yarok, the Desecrated Zaxara, the Exemplary Zimone and Dina