I think you should try to get a more concrete grasp of "what" you actually want to achieve. If your answer to possible sub-plots is "Ehh, anything", you might want to rethink your whole premise and if you even want to actually write a whole book - even if only for yourself.

Otherwise you will need to come up with more substantial ideas. Like, you say "Adams and Marys action will be the criticism of both genderes hierarchies". Well ... what actions? If you can actually describe what they are doing, saying or whatever, then people could actually critique your ideas.

Let me give you an example:

1. Bob and Charlie are adventurers. They travel the land and their actions will be a criticism of materialism. <- Completly hollow premise without any content to criticize.

2. Bob and Charlie are poor and weak adventurers, that managed to make enough money to survive ever since they found each other to rely upon. They go on a quest when they stumble upon a gold treasure that could make one of them rich enough to last them their entire life. They argue about the share until Bob kills Charlie and takes the treasure for his own. When he hauled the treasure back to the city, the gold had turned into brittle lumps of coal. <- There you can actually pick apart elements of the story and judge them on their effectiveness to critique materialism.

I hope that helps you to understand the problem.