At the moment none of us know what the introduction of Imagined housing will bring. But I'm pretty sure it is going to be great and I'm not worried for a second that it won't be. (ETA: When this was originally posted Test Houses had yet to appear.)
That said, there is the possibility that the forms of housing we now have access to, the homes we know and love (ok for some people "know and hate") will disappear, replaced with re-imagined upgrades. At a minimum, we are losing what we all know as a Quarter or street dedicated to houses.
With that in mind (and because I am an archivist at heart) I'd love to see an expansion of something that already exists, the model home. But in this case it would be a single street, maybe a seam street, in the style of the current yet soon-to-be-outdated housing streets, a Museum of Old Style Housing Street, containing an example of every style of dwelling available BEFORE the Great Housing Exodus (or whatever it will eventually be called.) Since housing streets will no longer exist as we know them, the street itself will be an excellent museum piece, a demonstration of form following function for those newer, younger Glitchen who are imagined after the Great Housing Exodus.
So one could enter the street and explore a brick for brick replica of the (soon-to-be-demolished?) apartment building that currently stands on Louise Pasture.
Further down the street one might enter the smaller apartment buildings as currently seen in the Swamp regions, or a Bog house, or an Alakol mansion or a Treehouse, a Cave dwelling or any of the wide variety of homes first seen along the residential streets of Groddle Isle.
This living museum would offer a look back at the type of houses we inhabited before we were able to imagine homes of our own, but also provide us with both a historical foundation and an inspiration to feed our newly gained imaginabilities. And like current model homes, if people wanted to squat there or plant herbs or vegetables and get all communal-like, YES!
And depending on which vendors get phased out, perhaps retired vendors could be let out to pasture here, converted to selling souvenir items from the Museum.
Finally, I would love to see at least one grainy old-timey film (a la the Rook Museum) of Glitchen going about their daily business in their quaint olde-timey un-imagined homes.
I think something like this would be a fantastic place to visit, a reference to consult when looking for inspiration when considering the many possibilities for the hopefully wide range of new housing options soon to come.