I think it might also be a matter of how much stuff, that is number of Hubs, you have on the site. My writing would be roughly the same 'quality-wise' now as when I started two years ago. I used to be in the 80s, now I'm up above 90 most of the time - at time of writing 97. The fact that I have 222 Hubs posted and around 35 people a day coming in for a peek (based on 16,000 plus viewing over two years) would have to have an influence.
So, keep writing Hubs if you enjoy doing so. Don't expect to get any worthwhile financial returns for it, though. For I'm pretty well convinced that out of 100 hits you'd be luck to get more than one or two would actually click on an advertisement.