There can be a creative tension between reform and change-the game approaches, if the focus is not on purity. 
Abstractions are guidelines and communication tools, not principles. Decisions are always connected to specific here-and-now situations. There is no principle that trumps all others. We are always balancing out one that is in tension with at least one other principle in the context of here-and-now needs, desires, and capacities.
For example, Ganas, the intentional community where I live, wants a diet of organic food for all the "right reasons," but we cannot afford organic food because we aren't going to violate our commitment to affordable housing. It would displace too many people and make Ganas only affordable to those with significant incomes. It is "the best" we can do at this time, which includes the limitations of our current thinking. A different community has different people and different histories and different dynamics. Therefore, they would resolve this conflict in a manner that is appropriate to them, not to folks at Ganas.
That's not a principle. That's reality: folks doing the best they can given all the stuff they have to make things work as well as possible in their context.
There is nothing to be pure about that is constructive, and there is no situation in which we know what to do because it is the right thing to do. Only a community or an individual can decide what she or they think is the best thing to do in a given concrete situation. And they should always be ready to change a decision, if the concrete reality is saying "ouch."
 "Changing the game is a long-long term approach. Think seven generations. Changing the rules is a short-to-medium term approach." See my previous blog for full discussion.