No, they don't. The reasons she gave in her speech are perfectly logical, ethically justified, and do not in any way make her less strong. To the contrary, they show she has the integrity and courage to put her family, her state and her country first and do what had to be done to deal with the situation facing both them and her.
As for your comment about "raising more questions", so what? Questions are fine, they're part of the process. So is speculation. It's pretending we have all the answers that is the problem. It's far too soon to know how all this will play out.
The lame duck excuse was just silly, as many others have managed to accomplish things during their last year in office.
The cost to Alaska was an interesting argument, except if the ethics complaints were truly frivolous as they appeared, the same people will be able to do the same thing to the next Governor — so what Alaska needs is to fix their ethics laws so people can’t spend Alaska into bankruptcy by filing frivolous charges.
Quitting for the ethics costs only makes sense if there is something special about her that makes her an easier target for the ethics complaints. Note that traveling a lot out of the state appears to be such a thing, but that would have been covered by her simply saying that she wanted to take a national stage and she couldn’t do that from Alaska and still serve her state.
Quitting because her family voted to have her quit isn’t logical or sensible. While I might well respect my elected representative using their sound judgment to make a decision like this, I didn’t elect their children, and I don’t really care if their children want them to quit or not. If I quit my job every time my kids voted for it, I would be penniless.
Quitting because of the attacks on her family doesn’t make sense, unless she is quitting politics. If they attacked her as Governor, they are going to attack her in any public role. The attacks were terrible, and we needed the media to wake up and call them for what they were. The people were getting on her side, and those who attacked her children WERE being called out.
But now she has validated their tactics — they wanted her out, and she quit. The next person they go after will have to work harder to prove the tactics won’t work on them.
Nothing about this was unethical, so I didn’t address that — I’ve certainly not called her unethical for quitting.