I'm afraid you misunderstand me, neither of these things are about exposure. They do not advertise, resteem or affect the visibility of your posts in any way.

Dustsweeper helps the people who visit and vote on what you are writing. That's why I suggest it. For example, this post here: I upvoted because I like what you have to say. Unfortunately, since my vote is only worth $0.01, it will be erased - the system will deem it "dust," unless it gets another 0.02 in upvotes in the next 3 days. The same is true for this post: - the votes you have received will become dust, and neither you nor your readers will earn anything from the interaction.

I'm not sure what exactly this Steemit thing is, but it seems to train positive habits. I'm using it the same as you: practice writing, see what moves me, and also to practice saving/investing.
Payouts from posts aren't really an income, but more like compounding interest.

You gave me an upvote worth $0.02 on my comment a few days ago (thank you!). Your readers and I might lose the interest on our upvotes to you, but you won't lose yours - because in 3 days dustsweeper will give that comment a 0.01 upvote (deducting that value from my dustsweeper account), just enough to meet the threshold built into Steemit.

I hope this helps to understand. I wasn't trying to sell you anything. I was actually offering to gift you a dustsweeper account, because doing so would benefit your readers (myself included!)