Your assumptions seem wrong.
There is widespread consensus that Donald Trump was put into power by the Russians. If this is true, his administration must do some favors for Russia.
The consensus is that Russia influenced the US election in Trump's favor (by eg hacking his political opponents and strategically using that information to influence public opinion; this may or may not have happened in coordination with some people from the Trump campaign). I wouldn't call this "put into power" though.
And this doesn't mean that Trump needs to do any favors. And even if we assume that it does - which I wouldn't - it doesn't mean that Trump can do any favors.
Instead of a quid pro quo, it is more likely that Russia assumed that Trump would be the better option for Russia based on his character and his pro-Russia stance during the campaign (this assumption may or may not be correct).
I also think that your focus on short-term benefits is not reasonable. A desire for a long-term weakening of the west in general, or NATO and the EU specifically, seems more likely.
There are a couple of actions that Trump took that benefit Putin and/or Russia in the short term:
- In 2016, the Trump campaign was responsible for removing pro-Ukrainian parts from the Republican Party platform.
- Trump legitimized Putin's re-election by being one of the few western leaders to congratulate him.
- Trump has not condemned Russia for the poisoning of Skripal, but instead invited Putin to the White House (his administration on the other hand expelled Russian diplomats and urged Trump to get tougher on Russia).
- Trump recently canceled further sanctions against Russia which were announced as reaction to Russian actions in Syria. Trump planned to remove existing sanctions at the beginning of 2018 as well, but he did not go through with them because of opposition from congress. The Trump administration refused to enact legally mandated sanctions against Russia at the beginning of 2018.
There may be others as well. Of course, these actions could also have been taken by Trump's predecessors (not as a quid pro quo, or because they are Russian moles, but because they see it as necessary part of foreign policy; this is true for Trump as well).
On the other hand, there are also a number of actions against Russia from the US (some enacted by congress, not by Trump or his administration). But again, a different administration - eg a Clinton one - might have enacted the same actions; or more likely tougher actions considering current Russian activities.
In the same manner, Vox describes Trump's Russia policy like this:
The root of the problem, experts say, is that what Trump says bears little to no relationship with what his administration actually ends up doing. Trump insists on treating Putin as a potential partner but doesn’t really use the levers of policy — diplomatic agreements, military deployments, and the like — to try to make this vision a reality. Instead, policy appears to be set by the American national security bureaucracy, which sees Russia as a rival and adversary.