Of the topic of development the new territories i think lake/swamp drainage is definitely one of developments thats is immediately needed but with greece having already drained lake copais has gains invaluable experience...with this experience the likes of lake karla should be no problem at all
Exactly, the drainage experience is there. Except lake Karla in Thessaly, there was a myriad of small swamps in the greek coastlands. Said coastlands were basically settled after 1830. Increased land reclamation will result in two major butterflies: fewer deaths by malaria and more land available. If you combine the fewer deaths with the very high birth rate (3,5-4%), then you have a significant population increase.
@Earl Marshal , check Socrates Petmezas, my go-to academic for the 19th century greek agriculture. "Academia" has many of his articles available for free.
Agricultural Change and Export Trade in Greece, ca.1830-1914
www.academia.edu
So, let's list some butterflies so far and comment on the repercussions.
(a) The issue of the National Estates was solved much earlier compared to OTL. This will lead to an earlier better development of the estates. If somebody knows that he actually own a plot of land, then he has the incentive to develop it. Said development is an arduous and slow process that I believe will pay dividends from the 1850s onwards. Terraces need to be raised, tree orchards planted (olive, mulberry, fig trees), warehouses and barns built, even rocks removed from the often poor soil.
(b) What will the 49ers do as an occupation? I doubt the vast majority will want to become small-time farmers. After all, a small-time farmer in Greece owned only a
fraction of what a small-time farmer owned in Germany. So, how many will try to squeeze a living out of 4 meagre hectares (or much less)? That leaves out three career paths: i) Public employees (military or civil), ii) Professionals or iii) Manufacturers.
Therefore, I see a lot of them getting involved in turning the greek agricultural products into manufactured goods to add value and export. The most prevalent of those will be wine, brandy, olive oil, soap, silk, leather goods (hello Epirotan pastoralism), cigarettes and in a smaller degree textiles. But how to find the capital to import the machinery needed for such industrial development? See below.
(c) The manner of the annexation of Thessaly will alter the balance of payments and the availability of foreing currency.
As the land has been liberated by the serfs themselves, we won't get to see rich Diaspora Greeks buying the chifliks cheaply from the Ottoman landlords. So, the rich and powerful won't get to lobby the government for extremely high wheat import tariffs. In that way, they were able to be absentee landowners and have a profit even with a small portion of the land cultivated with medieval methods, while they rented most of the land to semi-nomads for pasturage. The new smalltime owners will have a far better incentive to cultivate more of the land. But what does this surge in wheat production mean?
In OTL, grain took up 10-30% of the greek imports. If there is a robust wheat production, then there is much more foreign currency available to import machinery for factories or locomotives and rails.
Also, the annexation if before the American Civil War. The ACW lead to a temporary surge of cotton cultivation in the eastern Mediterranean, as the hungry Lancaster mills wanted more and more of King Cotton. Thessaly is good cotton land. Therefore, for some years the Greek cotton exporting merchants will reap huge profits. After America gets to export cotton again, what will happen to the thessalian cotton? In that case, it seems more profitable for the cotton merchants to become cotton manufacturers as they cannot achieve the previous profit margins and they have a big market in need of cotton textiles nearby (Ottoman Empire). So, we may eventually see Greeks buying ottoman cotton from Macedonia, Smyrna, Cilicia and Aleppo and exporting cotton textiles back to the Empire. Textiles that by the way, were the most valuable ottoman and later turkish import until the 1950s.
(d) We have a homogenous and larger internal market much earlier than in OTL. This undoubtly helps in industrial development, at least in the case of textiles and other light industry goods.
(e) In addition to (c), grain prices crushed from 1870 to the early 1890s (1892 specifically). So, even if Greece doesn't produce all the grain she needs, the rest of the imported grain is cheap, while the prices for currants are rising (until 1893 when they crashed), while the price for light industry goods (soap, cigarettes, textiles) are rather stable.
(d) The more diverse economy will handle the 1893 currant crisis much better.