In fact, high-level Communists were rich.

I disagree. As I mentioned, they did live better (more comfortably, higher consumption) than the peons, but not to the degree that I would call "rich". I don't believe that critics of communist regimes, both internal and external, called the party bosses "rich" either. For comparison, consider, say, corrupt South/Central American dictatorships.

Things have changed, of course. Putin is very rich.

the worrying part about rich people is that they can use their wealth to (1) do crime more safely, and even (2) change laws

You are worried about power, not wealth.

It's true that wealth can be converted to power -- sometimes, to some degree, at some conversion rate. But if you actually want power, the straightforward way is attempt to acquire more power directly.

There is also the inverse worry: if no individuals have power, who does? Is it good for individuals to have no power, to be cogs/slaves/sheep?