Well I really don't know how you adjust it. You don't want to reward every tom, dick and harry with immediate awards, just for showing up. At the same time, as a minnow, you're looking to increase your steem power, so if a spamish post nets 5 cents as much as your well reasoned blog, you grow faster with much less effort just by sloshing around your garbage trying to lure in some random votes.
Maybe you could weight the post based on the length, although there are ways to screw with that. Or even you could limit rewards for posts that have repeat content, some kind of algorithm to detect it, although this would be difficult as well. Could be that the whales would need to be incentivized to upvote lower rep members. That could be weighted on an inverse scale, higher rep equals a bigger knock to voting power/less reward and vice versa. There could be a way, but it will require some incentive change.