State of the world in the year 1500
Map of the known world with major powers marked
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British Isles:
Withing last 144 years Kingdom of England gradually conquered other states in region and it's dominant power there.
It is unlikely that Wales, although independent now, will survive next 100 years.
Gaul (Gallia):
After 144 years Kingdom of France managed to conquest most of Gaul region but not without problems. First one was lost war against England in which Kingdom of England gained strong foothold in Normandy. Second one was conquest of what was left of Burgundy by Austrians.
Next 100 years should be quite eventful with France trying to remove English presence in Normandy, Duchy of Brittany struggling to survive between two powers, and Austrian being kicked out of Gaul region.
Iberia:
There is only on power in this region - Kingdom of Iberia - which was created by Kingdom of Castile after conquering whole Iberian peninsula.
In next 100 years Iberia will most likely start to colonize Americas. The only thing that could end very successful Iberian Kingdom would be war with France or England.
Northern Africa:
Within last 144 years Muslim states in northern Africa has been replaced by Christian colonies. The most surprising one is Byzantine Empire which conquered Kingdom of Morocco.
Next 100 years should see some of former Muslim states gaining independence, but this time as Christian countries.
Apennine peninsula:
Peninsula is divided between three main powers. In the north there are Italian duchies which are vassals of Polish Empire. In the center there are lands owned by Kingdom of Iberia. In the south there is quite successful Kingdom of Naples. Between these three powers is the Rome, still owned by the Papal States.
In the next 100 years Naples will most likely conquer Rome. The future of Iberian footholds is uncertain.
Holy Roman Empire:
Holy Roman Empire is still a mess, although some attempts to subjugate HRE states by Polish Empire can be seen. Austria is the current HRE emperor but most likely will lose this title in text next 10-20 years.
Scandinavia:
Peninsula is divided between three powers. South-western part is occupied by Kingdom of England, north-western is owned by Kingdom of Norway, and the rest is under Polish suzerainty.
In the next 100 years England will most likely try to conquer what is left of Norway and Denmark unless stopped by someone.
Central and Eastern Europe:
There is only one power in this region - Polish Empire. Within last 144 years it managed to conquer or subjugate all Christian states. There was once quite successful Kingdom of Hungary, but after losing war against England and Austria it didn't managed to recover and it's on decline. Most likely will disappear in the next 100 years.
Balkans, Greece and Asia Minor:
Balkans region is... balkanized. Some parts are still owned by Hungary, some are occupied by Kingdom of England and Kingdom of Iberia, and the rest is owned by Byzantine Empire. Byzantines has seen their empire in better shape. At height of the power it owned Serbia, Greece and half of Asia Minor. But then English and Castilians came and conquered some Byzantines lands. Weakened empire was attacked by Chobanids which gained some land.
But there are signs of recovery within the Empire. Currently it's fighting against Chobanids and occupying all infidels provinces in Asia Minor.
Next 100 years should be interesting. If Byzantine Empire will manage to recover it will most likely conquer more Asia Minor provinces and maybe even retake English or Iberian ones.
And now things that I'm planing to do in the next 100 years.
First of all I will try to conquer Riga, it doesn't look nice inside my empire 
Second, I will try to ally with Iberians and then try to conqer English colonies in Black Sea.
Third, I will try to conquer the rest of Scandinavia including English provinces.
Fourth, I will once again try to subjugate Hungary.
And now questions.
What to do when reformation starts. Should I stay with catholic fate or should I convert to protestant? I don't know yet.
Where to expand? East or west? Expanding to east is much easier but western provinces are much richer. Currently I'm thinking about expanding westwards.
What to do with HRE? If everything goes well I will be the next Emperor. But I don't want to form HRE, I joined the HRE to be protected by the Emperor. The best option would be to disband HRE asap.