I believe that the Iranians would gain a lot from the Russian strategic partnership initiative, this would certainly make them even more resilient in facing any kinetic attack from the US and Israel, even though the Russians have their problems of lack of action in defending their allies and only their interests, a partnership at this strategic level is something that would hardly not be in their interest.
Ukraine could be piece of cake to next plan of third superpower, Turkistan, with projected zone of power from China to North Africa... Turkey is not ideal for anyone, but far more preferred than Russia and Iran, and with decreasing American presence in Eurasian heartland, full acceptable partner for usa...
This could be very dangerous for Iran and almost certainly fatal for half of Russian land...Without strong Iran, only Turkey is possible candidate to fulfill emptiness in the heart of heartland....
Iran is oriented to other zone of influence, so they can make pact of non-aggressive relations between them, Russian new doctrine have no problem with Iranian expansion on entire azeri state, while Armenia in Russian zone, but Turkish expansion is potentially fatal scenario...
It's far more easy with mutual efforts to neutralize rise of Turkish mega-empire, and very hard for solo-playing against it...
For now, Russians are ok, they transferred hi-tech air technology, they increased their presence in Syria, their military staff is in Tehran this days, and they informed Israel that will not accept any fatal scenario for Iran... And I am sure that more things are going on, but of course, only few people from both sides know whole story....
No love in geopolitics, but they have to cooperate now and in projected future...