Any details to share on baden baden countries economies? Which ones are doing good, bad etc. Any have any particular focus such as tourism. How intertwined is their economies to germany? Do they use german currency?
That's a big question and I can not really do it justice here, but I'll try a basic answer for the years 1908-1930(ish) first.
The new countries do not use the Mark, but their currencies are pegged to it at favourable exchange rates (favourable to Germany). The treaties give them the right to go on the gold standard, but none of them managed so that part is dead letter.
Who is doing well, who is doing poorly? Depends on definitions, in part. Wolhynia is technically doing very well, with a solid current account surplus and thriving trade, but its peasantry is effectively living a colonial existence. Estonia is in near-perpetual crisis mode, overindebted and overtaxed, but its industrial sector of growing rapidly and many citizens work abroad and send back remittances from Finland or Germany. I would certainly much rather be a farmer there. Poland is poor, but the overall figure papers over a massive discrepancy between the underdeveloped and semi-feudal east and the thriving cities of the west. Finland is basically divided between an urban, industrialising coastal region and a rural inland and northeast mainly focused on resource extraction. Life in Helsinki is not much different from life in Berlin. Life in Kola is not very different from life in Siberia.
In bulk terms, Wolhynia and Poland are food exporting countries, with strong seconds in semi-finished products (yarn, cloth, leather etc.). Finland is strong in timber, minerals, and semi-refined industrial products. Lithuania is a lot like a smaller version of Poland, but with a more maritime and trade-focused urban centre. Latvia and Estonia are trying to become industrial countries, but the way there is thorny. Latvia exports a lot of tinned fish. If anyone outside knows any one product of the country, it's smoked sprats.
Their economies start out completely integrated into the German wear economy and slowly begin to disengage as time progresses. The terms of the treaty are harsh, but it allows for easing and exits if you can pay for things and service debts in hard currencies. Earning francs or Sterling is a survival strategy.
One thing that we will see a strong divergence on later is welfare state policy. Right now, all those countries are fairly rural and fairly poor. public services are patchy and emerging. But Finland, Estonia and Latvia are putting sincere effort into a comprehensive welfare state based on the emerging german or Swedish models while Lithuania, Poland and Wolhynia are not. The issue is highly contentious in Poland and Lithuania (with a strong, heavily politicised rural-urban divide), practically non-existent in Wolhynia, whose governing institutions are dominated by landowners. All three countries will be latecomers to the game and their population suffers for it mid-century.
Basically, a village in eastern Poland and one in central Finland are very much a like in 1910. But by 1940, the Finish village will have a school bus service, a community nurse, a part-time post office with postal banking that pays old age and invalid pensions weekly, a telephone, and either a visiting doctor or access to a regional clinic. The Polish village will probably have one or two of these amenities, if any.