Difficult to say if any gains in the early 1700s would have translated to any long-term gains considering Russia's continued strategic vulnerability in Europe, which would have siphoned off the military elements (esp. soldier-settler Cossacks, artillery) most effective in the conquest of Central Asia.
There was also no specialized bureaucracy/lobby group for Russian C Asian expansion in the early 1700s and so the country's focus was still largely down to the whims of the monarch. Anna and Elizabeth saw Russia's mission in C Asia as Christianization and Russification while Catherine the Great preferred to leave them be. Neither saw C Asia as particularly important; Russia's interest there was really only entrenched after 1) the surge of Slavophilism in the 1800s, 2) the advance of Britain in India which demanded a corresponding Russian response, and 3) the emergence of bureaucratic groups that provided roadmaps for Russia in C Asia, starting with proposals for Kazakh administrative reform in the 1820s.