Napoleonic Wars: Wagram, Friedland, Eylau etc. Even for Napoleon's decisive or strategic victories, the stronger the victory, the harsher the peace terms that could be imposed and the less likely said country enters the war against Napoleon again. Especially if state is made an absolute puppet, annexed or dismembered into pieces. Borodino might be an opportunity to destroy the Russian Army while Lutzen and Dresden could be more decisive to secure Napoleonic victories.
Crimean War: Successful assault on Saint Petersburg or a faster Crimean and Sevastopol campaign.
Russian-Turkish or Balkan Wars: Exploiting victory with an assault on Constantinople if victory is stronger and earlier with less fear for Ottoman and diplomatic consequences.
After 1900 [if allowed]
WW1: Battles of the Marne and East Prussia had the potential of destroying enemy armies and worsening the retreat of the vanquished. Better performance at Gallipoli would strengthen the Ottomans and weaken the enemy for the coming campaigns and the same can be stated for those on the western front.
[For the former, WW1 ends earlier in 1918 with the Germans controlling less of Belgium and France and/or more of the Russian Empire with a better performance in the east. Latter provides effects for independent Turkey and the Middle East if not impacting WW1.]
WW2: Many battles. [Dunkirk resulting in the British Expeditionary Force lost, a better Battle of Britain, Operation Compass exploited and being faster, Crete with less paratrooper casualties, Barbarossa battles, more damage on Pearl Harbour and troops captured by Japan, an American carrier saved and/or one more Japanese carrier lost in 1942 battles, more Soviets encircled in the lead up to Stalingrad and Kursk or Germans during and after the battles, battles for the Marianas and Leyte Gulf with a more aggressive pursuit of the Japanese forces, Ukrainian campaign, Operation Bagration and subsequent Soviet offensives destroying an extra German army group or making more communist nations, D-Day, Italian and Western campaigns and pursuit encircling more German troops in the west and getting the Allies into Berlin, weakening the Soviets and more decisive Soviet exploitations of Polish and Balkan victories, less costly Pacific battles and an earlier nuclear bomb.]
[Excluding pyrrhic and indecisive or not strategic victories.]
Too many battles to list, seriously.