1. Xebec wasn't holding back and they were normal people compared to the giants. In RPG terms, it's like the spell False Life, it's a health boost atop of what you have.
2. Because that's simple storytelling of not going overboard. Because he did it again this arc and it's not wise to to the same trick in two arcs, back to back.
3. Their regeneration isn't exactly like a Logia. So Killingham was separated away from his limbs. And for the time being, we should only assume Super Super Sommers has that heart.
Well, that wasn't too hard.
2. Because that's simple storytelling of not going overboard. Because he did it again this arc and it's not wise to to the same trick in two arcs, back to back.
3. Their regeneration isn't exactly like a Logia. So Killingham was separated away from his limbs. And for the time being, we should only assume Super Super Sommers has that heart.
Well, that wasn't too hard.
2. It doesn’t even cost Imu anything to manifest through Saturn or the other Gorosei, there was literally no in-verse reason for him to not do that, given how important the Egghead mission was.
3. Super Sommers straight up regrew his hand that got cut off by Gaban’s ACoC strike, he didn’t reattach the lost hand. HKs suddenly needing to reattach their separated body parts instead of just regrowing new ones is a blatant retcon