In mine, titled
Oikoumene, Alexander lives 14 years longer, to just three months shy of 47. I conducted a search here on AH.com, counted up the opinions of everyone on how long Alexander would live if not assassinated, and came up with that number.
For the rest of 323-22 BC, Alexander the Great remains off the war-path, instead dealing with angry Macedonians, consolidating his power, paying off his soldiers and organizing new armies to hold down his large Empire. He plays the Shahanshah role.
In late 322 BC, however, word is received that a rebellion had begun in Alexander's Indian satrapies, led by a prince named Sandrocottus (Chandragupta Maurya). Alexander gathered his armies once more, including more Persians and less tired Macedonian veterans, and arrived in Alexandria-in-Arachosia by mid-321 BC. There he quickly re-instated Macedonian authority after a battle in Taxila and other skirmishes along the Indus. Sandrocottus had turned and fled from the Alexandrian frontier, turning on the Nanda Empire, which, though heavily armed, was corruptly led and taken easily.
By 320 BC, word was received that the northern and central Greek cities, led by Athens, had erupted in rebellion against Macedonian oppression. So too had Cappadocia and other client states. Alexander led his armies back west to re-assert his power. By 319 BC his empire had absorbed rebellious states along the Black Sea, while he also oversaw the execution of many rebellious leaders throughout Greece, and the annexation of Epirus. Craterus had been building a navy, for use in an Arabian Campaign, as well as a future war against Carthage. Alexander decided to experiment with his new ships by launching a war of conquest against Sparta, who he viewed as responsible for fueling the Greek rebellion, as well as Crete, Cyprus, and Bithnyia. This took a full three years.
Alexander and his armies took another hiatus from 316 to 314 BC. He was getting older and more eager to consolidate his empire for his seven year old son and heir. He facilitated a new naval building program, the building of large temples throughout his empire, as well as continued experiments in mixing his European and Asian citizens. He brought populations from the East, mostly children and women, farther to the West, while sending soldiers and their families to his cities in the East. It wasn't very popular, and Alexander did not put as much effort into it as he would have liked.
While he had planned on launching a campaign to conquer Arabia, Alexander was delivered news that his satraps in India had begun conquests of their own against the Nanda Empire, which had been weakened by an attempted invasion of Sandrocottus, which nearly succeeded in toppling the empire. The weakened empire was ripping by its seams, and its large, formidable military that Alexander feared against going against had splintered. Alexander gathered his armies in the west, mostly Greeks, and journeyed once again to the east, depositing many of his soldiers throughout his acquisitions in the East, and exchanging them for Persian soldiers.
By the time Alexander arrived in India by 313 BC, his satraps had already made several gains. He congratulated them, but would later replace them for fear that their popularity would work against him. He finally launched himself against the Indians, and in the vacuum of power and disdain against the Nanda, his conquests were easy. He established large Indian satrapies over his gains, which was largely completed by 311 BC.
In his stead, Craterus had launched a campaign against Arabia, launching his ships against the states and bare populations along the coasts of the Red Sea and the Persian Gulf. Alexander would return to Babylon by 310 BC to view his accomplishments.
A bout of weakness had dehabilitated Alexander the Great by his return to Babylon. For the next year, he would become more and more sickly. As such, by the time of his death in April, 309 BC, Shahanshah Alexander had already moved pieces around to ensure the legacy of his empire. New lords and officials were shuffled around, there was a large, final population exchange between Greeks and Persians, temples were ordered to be built, his son was proclaimed to become heir to his empire, with Craterus as his regent until his son reached the age of 20 (in the year 303 BC).
Alexander left his empire in one piece.
Plausible?