Didn't really get anywhere except one weird idea that:
Morrigi research to Addict other species might be unique in that it comes from or at least has its beginnings in research on the effect of a vast amount of easily-obtainable alien plants (that might have survived the difficulties that the Morrigi civilization has gone through, and still grow on their planets, hence are easily obtainable compared to getting them from their original source) and their chemical extracts on alien species.
Many of the plants (remember some Tarka like chocolate milk and Hivers like and eat cheese, see The Deacon's Tale, so alien cuisine is already a trade item) from the thousands or whatever worlds the Morrigi visited at the height of their empire might still survive somewhere in Morrigi civilization today, if enough farms/gardens on a Morrigi planet(s) survived. Erinys has written:
http://18.104.22.168/forums/viewtopic.php?f=9&t=9677&p=275318Erinys wrote:This would depend on where the Morrigi are setting up shop and what the purpose of the settlement may be. Morrigi females are capable of stealth and of living underground; if they know they must not be seen, they will tend to carve out a hall in a mountain or cave in some remote and inaccessible wasteland. Under such circumstances they will conceal their operations as much as possible.
A normal colony however is laid out even from the first days with the buildings and their associated lights in a pleasing pattern which is meant to be seen from above. Morrigi towns and cities are usually easily visible from orbit, and often have a lay-out reminiscent of a magnified crop circle or the lines on the Nazca plain for this reason. The colorful glyphs help to identify the women who live in the area and serve as markers for their husbands and brothers. When there are men in orbit, the houses often light up their roofs with celebratory torches or electric light shows. These are very beautiful and have a festive air.
Flashing patterns of light also help to communicate a colony in distress or serve as a warning beacon when Morrigi women need to warn their husbands to stay away, as in times of plague.
So in a similar vein, gardens could decorate Morrigi female dwelling because they could wow the (rough analogy here) city-boy Morrigi males who Descend to the planet. Who are already familiar with Morrigi architecture but don't get to see much planetary wilderness in outer space (where space is at a premium so maybe the organic waste recycling might be done by algaculture to avoid the "free-range grass" (in this case, a different farm crop and/or a farm animal) space problem faced by herbivores in outer space). So large collections of plants may be rare for the Morrigi Males to see in "urbanized" outer space, except maybe on Civilian Stations, but that is more like Central Park, not "the country" of a planet. Since "the country" might be something new and exciting for pretty much any young male if he does not remember his childhood very well because he got shipped off-planet to live with the males once he fletched (pretty young I guess), or if that's not the case at least "the country" the Morrigi females' property might bring back pleasant childhood memories for the male and give a good first impression of that specific female's dwelling on the planet, and the male might appraise the wealth of the female first-hand after his Descent. Which gardens and landscaping can be a part of.
So some sort of garden or landscaped area near a female Morrigi dwelling might be very common. That might have a few spices, fruit plants, etc. in it. Especially if the Morrigi female personally likes that kind of thing. So even if the major food-producing farms were destroyed, maybe the alien plants in the surviving gardens around the surviving female Morrigi dwellings could survive (or at least their seeds, if the surface was entirely obliterated but some buildings survived). Even better, plants are easy to keep around because they self-replicate very cheaply so unlike the lost Morrigi technology they are much easier to keep around.
So the Morrigi research for Addict whichever species in SotS might involve a government project (depending on whether or not the private sector already did this) to test (or maybe rediscover if this was known at the height of the Morrigi Confederation) how alien species react to the alien plant leaves, seeds, flowers, etc., the boiled extracts of those, and other cheap methods to mass-produce a plant-based product, to find cheap spices, perfumes, incense, etc. so unbelievably awesome to that alien species that they just fork over money to buy it. There are many examples in history of things like tea (ex: East India Trading Company) and spices being quite profitable. The Morrigi could also try to alter the plant-based chemicals to improve their addiction qualities if necessary.
And as a side note, those Morrigi females who took care of the plants (even as a hobby for their garden), if they survived, would know the uses of those plants for Morrigi (though probably not for alien species) so Morrigi cooking even in SotS 1 might be kind of awesome with the selection of spices that their own species likes?
That's my wild speculation. I'm hungry to get back to my rented room and have supper now (I really like spicy food).