Preferred COAs for Germany, year-by-year, if that year is the PoD:
1871 – If you can swing being nice, by restraining internal demands and enthusiasms, do not annex Alsace-Lorraine. Also, do not coronate the Emperor at Versailles. Coronate the Emperor either in Germany (at Aachen, or any border city attacked, or Frankfurt; or if in France, at Sedan)
1871 – Alternatively, if you can’t swing being nice, and there must be annexations, take a little more. Take the Briey-Longwy region, and possibly fill in the A-L bend up to the line of the Meuse or Moselle river.
1873 – When setting up the Three Emperors League, try to make it broader, into a Four Emperors League, including the Ottoman Sultan.
1875 – Actually go to war with France in the spring/summer. Upon victory, charge another indemnity, seize Briey-Longwy and up to the Moselle. Try to get Italy as an active ally. If so, gain territorial concessions for Italy.
1876-77 – Work in parallel with Austria-Hungary to warn off Serbia, Montenegro, and Russia from launching war against the Ottomans in support of Bosnian and Bulgarian revolts.
1877-78 – When Britain and Austria get hostile to Russian war on Turkey, probably during defense of Plevna, negotiate alliance with them to make an unacceptable ultimatum and war on Russia; if they refuse to fight, switch sides and support Russian peace demands completely.
1881 – Urge Italy to move on Tunis as fast as France. If France opposes, support Italy to the point of war. Upon victory, charge another indemnity, seize Briey-Longwy and up to the Moselle. Gain territorial concessions for Italy in Tunis, the Alps, and Corsica
1885-1889 – Attack Russia, in league with Austria and Ottomans. Defend vs. France if needed.
1890 – Keep reinsurance treaty
1890s – Keep building up ground forces, especially after Franco-Russian alliance; Attempt, discreetly, colonial deals and swaps with Britain, Netherlands, Belgium, to minimize crossing colonial paths with Britain and maximize crossing colonial paths with France.
1890s – Woo Ottoman Empire
1890s – Keep mouth shut on Transvaal
1897 – Take Ottoman Empire’s side against Greece in Greco-Ottoman war, to signal, hands off the empire.
1899 – Accept Britain’s alliance offer, even if it is Far East based and less than ideal or immediately useful
1903 – Accept Russian alliance offer when Russia is open to it
1905 – Attack Russia shortly after Tsushima, with the Navy and Army, in League with Austrians and Ottomans, set up a ribbon of border states. Defend against France in the west.
1906 – Immediately set to work trying to bring the Ottomans into the Triple Alliance
1908-1909 - Attack Russia, with the Navy and Army, in League with Austrians and Ottomans, set up a ribbon of border states. Defend against France in the west.
1908 – Alternatively, with advent of Triple Entente, cut loose from alliance competition, and cut loose from sole reliance on Austria-Hungary. Therefore, decline to support Austria-Hungary on Bosnia annexation, at least unless there is unanimous German, Italian, Austrian consent. Actually, thenceforth use the consent rule to rein in both of them, or disavow both of them.
1911 -- Forcefully diplomatically oppose Italy's plans for war against the Ottomans behind the scenes. First goal is prevention of war. Secondary goal is to gain Ottomans as an ally.
1912 and on - avoid initiating war at all costs for as long as the Triple Entente is a going concern.