Good summary of the debate, Hadey!
Personally I am a pro choice person. Have seen this tradition being celebrated in the right spirit for a long time and i have witnessed its evolution to some extent as well. I for one would indulge in it depending on my mood and mindset at that particular time. But I have immense respect to anyone who keeps it as I understand from where they are coming from.
As far as it's misuse is concerned , well , the blame like you have mentioned doesn't lies with its concept more to do with the mindset of the people and how they interpret it. They will find hundred other ways to harp on the Patriarchal bandwagon. The solution to this point is not in diminishing or dismissing traditions like say KarvaChauth/Raksha Bandhan but in making a healthy evolution of their practices with changing time. This way will be more organically and long lasting.
First let's ask ourselves where exactly the pain point lies. Is it the fasting? Say, a couple of women were to simply pray for their partner's long life, would it be acceptable without any qualms?
I doubt it matters in anyway, won't it question the faith of an individual and his way of worshiping. if a woman is comfortable and is in a healthy condition to fast then should we object it.
And if these women were to do it silently, without much drama and without any pomp and show (gatherings, gaiety, celebrations, sieves and reflections) would it make it better?
Why would it make any difference, the scale of celebration in no way reflect or measure the equality of gender or the impact of this on a woman's Psychology. Too much cultural censorship?
Honestly, I feel the problem is much bigger and irrelevant to Karwa Chauth, if a woman is suffering from gender inequality or from a sexist mindset then a festive like it, might just be a usual vessel for her abuse not a precursor in any way.
That is why I suggest traditions like Karwa Chauth should be used as a way not to remind us of gender inequality but to use it as a platform and empower women about themselves. And remind them that its their choice and right to enjoy the day as they feel like.