I didn't know where to post this, but what the hell. Here it is now. All you need to know is that this place will be (at least, I'm hoping it will) be a dumping ground for all the map challenges that people want to post. I'll inaugurate it with this old map that's rotting in my computer:
How did I get this? (Year is 1947)
Mehmed II and his heirs look to Italy instead of the Middle East. They kick Spain out of the alt-Italian wars, and make Hungary a Vassal state. Spain, now on the defensive puts more effort into making the union with Portugal work but cannot hold the far-east colonies and remains an Atlantic power. Since they never see themselves as "holding the line against Islam" (because they are not in Italy)a civil war between Constitutional and Absolute Monarchy erupts and some colonies break away. The Absolute monarch losers flee to Mexico and continue their empire there while the Constitutional Monarchy of Spain adopts more liberal laws and keeps some colonies while remaining on good terms with its former colonies.
Trying to keep the light of Imperial Spain (true Spain to them) alive, the Mexican Empire helps Cascadia break away from Vinland to keep the Columbians from getting to the sea and making the Mexican Empire and its Alt-Nicaraguan Canal the only way for the Columbians to gross to the pacific ensuring massive revenues and probably ally with Britain against the former rebels. Hungary being hostile but not Ottoman, means Austria focuses on OLT's Germany area. As Austria uses the Ottoman threat to gain power in its territories and the north german states unite to hold them off.
In Scandinavian, Sten Sture is killed at Brunkeberg and Denmark retains hegemony in Sweden, parlaying it into a permanent union in alliance with the north German states, perhaps birthing a Alt-Protestantism. Allying also with the Lithuanian-Polish Khanate, they successfully focus on expanding into the new world but cannot full control the far west.
Britain while colonizing the Americas, outlaw slavery--however this causes a colonial to revolt except for New England and surrounding areas. Britain then competes with a hostile CSA (Columbian States Alliance, an alternate name for them) and proceeds to colonize other areas looking for replacement materials and sources of capital in hot competition with the Ottomans. They ally with the Mexican Empire.
The Franco-Ottoman alliance eventually breaks down when the Ottomans begin to expand eastwards uniting almost all the Muslim world and treat France like a junior partner. France instead allies with Constitutional Monarchy Spain to check British influence in Africa and attack the Ottomans.
In Asia, a weaker more religious Russian Empire is forced eastward keeping the lands it can against a more aggressive Ming China. The increasing power of Ming China forces Japan to modernize with the times instead of closing itself off and it seizes Korea. When the Ming Dynasty recovers after the climate disasters of the 1600s (because the Manchus are battling an encroaching Japan-Korea), the Japanese find they cannot stand against Chinese power and lose Korea--the Koreans while not loving the Chinese as overlords prefer them to the Japanese. Over time Chinese business interests effectively make Japan a client state and forcibly incorporate it into a greater Asian union.
In this world the power blocks stand as:
Britain
Mexico
Cascadia
Ottomans
Hungary
Scandinavia
N. Germany
v.
Iberia
France
Austria
China
Vinland
Columbia and Russia lead a power block of non-aligned states but neither have mobilized resources efficiently, the Russians because they lack the manpower and have ethnic sectarian issues, and the Columbians because of retarded technological and industrial progress based on their long-time acceptance of slavery, perhaps outlawed in recent memory.
Lithuania? Probably plays off Russia+British Powerblock so is not officially aligned with Britain.