I also suspect a part's played in Steam not categorising titles well enough to appear in people's feeds. I own a number of shmups and regularly see them under "games I might like" but noticed Inferno 2 was categorised as being action/RPG. Maybe there'd just not been enough people to play it for it to draw that mathematical conclusion, but the point still kinda remains... how do you get people to notice?
I suppose a better way could've been to release a thinly-veiled content update to a number of the Radiangames titles on iOS, including a popup for the game. I know that sure as hell would've worked, even if I didn't play the games (sometimes just seeing an app is updated is enough to get me to play it).
At least there are several outlets dedicated to mobile gaming where they can get some kind of publicity, like he mentioned. Nothing really exists for that for the Steam indie market. I suppose Beril would be one of the few people here (and maybe whoever it was that made Cook, Serve, Delicious!) that could give us some insight.