I wouldn't necessarily call it bad writing, but it did seem a bit pointless.
Tsunade was on the verge of death, and many believed she would make some sort of noble sacrifice to revive the other Kages, along with leaving the Hokage spot open for Naruto. The fact that she could simply be revived without any obvious side-effects makes a bit unbelievable, especially since most other characters that died suffered from much less severe wounds.
Hopefully their revival will lead up to a good pay-off in the future. I'd hate to see Kishi do something like this just to solve the issue of what the villages would do if their Kages all died in the war. It would seem like the laziest option in that case.
Tsunade was on the verge of death, and many believed she would make some sort of noble sacrifice to revive the other Kages, along with leaving the Hokage spot open for Naruto. The fact that she could simply be revived without any obvious side-effects makes a bit unbelievable, especially since most other characters that died suffered from much less severe wounds.
Hopefully their revival will lead up to a good pay-off in the future. I'd hate to see Kishi do something like this just to solve the issue of what the villages would do if their Kages all died in the war. It would seem like the laziest option in that case.