There's about 60,000 comments on this post already, so forgive me if this has already been pointed out.
Note that it's not just whale investors who can get a lot of steem power and have powerful votes; the platform is intended to increase the voting power of good voters (the curation rewards). If you curate quality content, the platform pays you steem power which increases your voting strength.
So if you want to have a greater say in what content gets promoted, and you don't have a lot of money sitting around to buy steem with, then either post quality content or keep an eye on the new posts and upvote the good ones. Over time your steem power will increase, and you'll have more ability to promote the content you think is important.
Indeed. This makes it so that even people that don't have the knack for content production can still participate and earn by curation. There are no excuses for failing to develop yourself here. There is no barrier to entry and anyone can build up steem power if they just work at it consistently.