Interpretivists and positivists
I think Julka and I fundamentally agree that our work falls into the interpretivist camp although I suspect we came to this realization through different paths. (Certainly her path involved more of an academic underpinning.) I came to design first through practice. It was only later, in graduate school, that I undertook a discussion about the possible theoretical frameworks that might inform my approach to design and research. Even then I undertook them with a knowledgeable guide who had climbed the mountain many times before and laid the map of options out in front of me, so my ability to speak the language is still pretty stunted. Still, for me, discovering about and understanding the world is fundamentally about narrative and stories; breaking them apart and putting them back together. Like Julka said, people are really really complex which is what makes them so interesting.
As a person who spends her days at an institution with a positivist bent, I think there is an interesting conversation to continue here about how different research types co-exist and work together, but I will drop it for now in favor of Julka's other question.
What can a design collective contribute?
I am going to suggest two things that design (and by extension a collective) may have to offer.
1) Making. Designers bring to the table the skills and an inclination towards moving beyond understanding to the act of creation. This can be applied at the information gathering or information sharing stages.
2) Sense-making. Julka makes a great point that there is a vast amount of research addressing in this case money and the human condition from multiple disciplines. What seems to be missing, what a design collective may be able to offer, is a method for pulling that information together and making sense of the amassed information. In this view, design research serves less as a formal research discipline and more as a supplemental strategy for understanding the topic and helping to form frameworks into which other research is synthesized.