The challenge is that there's so much that could be done. As withneedle suggests in comments for part two of this series, you could do econometrics regarding genre creation and production (and Google ngrams makes that possibility all the more fascinating); you could look at character choices through the lens of economic behavior, taking into account that economic behavior encompasses far more than the obvious questions of to buy or not to buy, to invest or not to invest.
In order to make the class most useful, however, I think that it's necessary to find a way of making the integration of lit and economics into a sort of narrative in itself, something that helps avoid the combination simply becoming a gimmick. Narratives aren't an unmitigated good -- the inherited narrative of conflict between literature and economics has done plenty of damage -- and yet I think the best way to counter that damage is to show that different narratives exist as well.
The idea is that literature can help us understand the history of the discipline of economics – how it might have become an art, but instead became a science, and why it has remained a science. This is a slightly different way of looking at Mary Poovey's positioning of imaginative writing as a genre whose original purpose to help mediate value -- if she's correct in doing so (and I think she is), then the implication is that looking at how literary texts confront economic issues differently over time will naturally lead to understanding more about how the discipline of economics, and its cultural context, changed over time. A sustained course of study in lit. and econ. couldn't replace a quarter spent reading David Ricardo, Jeremy Bentham, James Mill, J. S. Mill, William Stanley Jevons, Carl Menger, and Alfred Marshall -- but neither could that course replace one mixing those economists with Ruskin, Dickens, Harriet Martineau, and Charlotte Brontë (or any other combination of literary and hard economic writers).
Today we see imaginative writing as an art, and economics as a science. Whether economics is actually a science, or will remain one, is a question that's been posed implicitly for years in any comment that implies that it takes mysterious talent or arcane knowledge to prosper using economic knowledge. It's posed more directly by David Brooks in a recent NY Times op-ed, which is then dissected by the late Maxine Udall. Notably, Brooks' idea that economics will "blow up" as a field centers around the role of mathematics vs. interpretation (or as Brooks puts it, "a subsection of history and moral philosophy"), and how important each one of these approaches is to producing economic knowledge.*
I think what Brooks is missing, or not addressing, is that the conflict that we're facing now is an echo of debates surrounding the emergence of the discipline of economics originally, both in the eighteenth and nineteenth centuries. For a long time, depending on the author, a treatise might have an approach that was grounded more in mathematics, or in theory. By the mid-nineteenth century, economics was being discussed and written about as a science (and for that matter, "science" had taken on the meaning that it has in contemporary usage). In 1895, the London School of Economics and Political Science was founded; by 1901 it had been recognized as part of the University of London, and its degrees of BSc and DSc recognized as the first university degrees oriented towards the social sciences. But economics did not become a science, and has not remained one, without conflict.**
One of the costs of remaining a science is that economics has to display a different perspective on data than it would if it were an art. You could do an interesting study on the querelle des anciens et des modernes as it works differently in the arts and sciences, I suspect. But literature’s status as an art, its perspective on looking at information over long periods of time, and from different perspectives than economics, is one of the characteristics that makes it a useful platform for looking at economics. It avoids the tendency to look for norms and averages, and to make assumptions about whether aspects of economic livelihood are endogenous or exogenous (see Udall). It's why the two disciplines need each other.
* David Brooks is not an economist. Udall was, and she defends her discipline against the prediction that it will explode by acknowledging that in order to progress as a science, practitioners of economics need to diversify our methods for "conceptualiz[ing] and relat[ing] our theories to real-world phenomena."
** Just for giggles, check out the Google ngram for "art of economics." It's not as precise as I would like; for one thing, it's hard to tell exactly where single years match up with spikes in the data. But I do think it's interesting how it spikes up and down, and how several of those spikes seem to coincide with memorable financial crashes.