If Russia and Iran are friends of convenience, it is because they do in fact have a shared interest: anti-Americanism.
If Iran was ruled by a pro-American government, then the anti-American Putin would be hostile to them as he is hostile to all of America's allies around the world.
You say America is a servant of the Saudis, but you seem to have a bunch of excuses for Putin's slavish devotion to serving the Iranian jihadist agenda and making sure they get nukes.
Why is it that the people who blame America first always seem to have a bunch of excuses for why our enemies ally themselves with jihadists against us, and explanations of why they are right to do so?
I don’t know why you assume that an Iranian government that was quite simply not hostile to America would automtically be “pro-American” in any sense, by a Russian view or otherwise, when such a state is not necessary. India for example is not hostile to America without necessarily being “pro-American”.
Second, I am no fan of Putin and I recognize his government as a type I call a mobacracy. However, I aslo see that as fact that represents a deeply rooted cultural element of Russia, which began in the earliest days of the Russian czars and has not changed over the centuries - a culture with a very high, and very embeded acceptance and tolerance for autocrats.
Russia, like the U.S. seeks as much influence as it can over/with its closest neighbors, by all means, friendly or otherwise. However, with but a few exceptions, the vast majority of former vassal states are not now nor willing to be Russian vassals, and Russia is not going to threaten any of them with its nuclear arsenal, and the Russian economy, demographics and military abilities represent right now a dimenishing cability for empire building.
Influence, partnerships and such yes - empirial domination is not in my opinion in the cards.
Lastly, like the U.S. with respect to central and south America central asia IS THEIR NEIGHBORHOOD.
Shall we refer to U.S. interests in our hemisphere as imperial, just because we seek such influence out of our own self-interest?