There are several specific sectors of the Russian economy that should be considered. I'll go back to the recommendations by the Atlantic Council, which were mentioned here. They specifically encouraged western powers to think of major Russian banks, which are crucial for the Russian economy and which some people in the Putin circle have a lot of personal interest in.
Second, I would think about the sanctions connected to the Russian commercial activities in the Black Sea region. Also, I would explore all the opportunities that the Magnitsky act of Canada provides us with.