I think for now #3 is the stance you need to stick with. I think you are getting ahead of yourself with all the rest of it. If #3 doesn't get accepted, then #1 is pursuing, and I think #2 is an outgrowth of that decision.
Don't run ahead and start fixing the problem. I'm not saying there aren't things on your end to fix. But the major fixing needs to be done on her end. Until you have willingness to stop digging the hole you are in, you can't fill it up. And she is actively digging.
The ball is in her court. You can't keep hitting it. Once she says, "yes, I am willing to try to make things better", you can move into the next phase of coming up with ideas to make it better. But that is different than if she has the attitude "I am willing to stay if things are better without any effort on my part." That isn't good enough.
The brainstorming is good. But she needs to participate. Maybe read a marriage improvement book together (take turns). We used "After the Affair" by Janice A. Spring. I'm sure there are lots of good ones. You say she doesn't like the exercise of what can you do nice for me. OK, so don't do that one. Find another. Probably she doesn't want you to do nice things for her because she doesn't want to try. Which is why your first and only goal at this point is to get a commitment to focus in, and try.
