Sisko is my favorite. I don't think it was going off the deep end as much as using the same strategy the US used by nuking Japan. Japan had no chance at that point and continuing conventional war would have been more costly in terms of lives lost and property damage. Using nukes crushed any hope they had of continuing the war and have their prideful government an out that preserves their ego.
In DS9, it sent the message that the federation is can and will annihilate the dominion to defend themselves and the god complex of the changelings was pure delusion.
I don't like the phrase "no excuse". I'm a particularist. E.g. There is no excuse for shooting someone. Shooting a person actively shooting up an elementary school is fine in my book.
I'm in the middle of my DS9 rewatch and totally forgot about the stark difference between Sisko hair and Sisko bald. I just watched the Homefront/Paradise Lost episodes and the episode where Eddington defects to the Maquis and watching Sisko go all badass and lose his shit was fantastic.
Much as I like Avery Brooks, he never got a handle on the Sisko character until he shaved and went back to being Hawk but with a son. They should have let him do that from the beginning.