A more limited Soviet military intervention in Afghanistan

Of course, a rivalry between Afghanistan and Uzbekistan can certainly occur in this TL; indeed, such a rivalry might very well (at least initially) make Uzbekistan more dependent on Russia and to agree to Russia-led integration schemes/programs in exchange for large-scale Russian military aid and assistance to Uzbekistan.

But Tajikistan share a larger border with Afghanistan than Uzbekistan.

Also, for the record, I think that Pakistan will probably win a proxy war (with Iran) over Afghanistan due to Pakistan probably being willing to commit more resources to this. Of course, the interesting thing would be if Pakistan-supported Pashtun Islamists in Afghanistan in this TL will still eventually allow Islamist terrorist groups such as al-Qaeda to have a safe haven in Afghanistan; indeed, if a 9/11-style terrorist attack still eventually occurs on U.S. soil in this TL, I can certainly see the U.S. making a deal with Uzbekistan (the Soviet Union would have probably still collapsed by that point in time in this TL) to allow the U.S. to use Uzbekistan as a base for invading Afghanistan in exchange for U.S. recognition of Uzbekistan's sovereignty over northern Afghanistan and in exchange for large-scale U.S. military aid and assistance to Uzbekistan.

Well of course Pakistan would win a the War, they have the backing of the United States, also a smaller Afghanistan would be more hostile to the outside world who it might claim did not when the Soviet Union annex part of it country, a perfect breeding ground and location for terrorist organizations who support the Afghanistan government view.