Yes, one needs to think carefully about code changes. One of the results of game theory is that bad actors can never be wholly removed from a system, but their rewards can be minimised to the extent that they do not create a "bad system".
In the film The Matrix, the Architect describes that the system has gone through a number of iterations; none of them perfect but converging towards some optimal goal.
Apart from changing a few obvious parameters, the Steem economy has not seen significant iterations. And as we have seen, those parameters are not sufficient to change the economy; they have merely changed the profitability of bad actors. "Bad", as always, refers to the tendency of a system to converge towards some fixed point whereby bad actors become significant.