Perhaps to some degree, different karma coefficients could be used to support what we consider useful on reflection (not just on impulse voting). For example, if a well-researched article generated more karma than a month of procrastinating while writing comments...

There is some support for this: articles in Main get 10× more karma than comments. But 10 is probably not enough, and also it is not obvious what exactly belongs to Main; it's very unclearly defined. Maybe there could be a Research subreddit where only scientific-level articles are allowed, and there the karma coefficient could be pretty high. (Alternatively, to prevent karma inflation, the karma from comments should be divided by 10.)