Absolutely, yes! Kaveh's self-heal is quite potent, and you can easily get by in a Spiral abyss chamber without using any healer at all. However, that might not be sustainable on higher floors, as the enemies become tanky and have fierce attacks. Some enemies can one-shot your characters and have invulnerability frames and multiple phases, which makes them hard to kill. It's better to have a healer on your team to mitigate incoming damage.