Valve's cuts are fine. I remember the times when developers were glad if they got 20-30% of the profits in general, with publisher deals starting at 70% cuts for IP-first game releases, and way higher if it was your first game. This after you pitched the game with a tech demo running, of course. Steam is a blessing on digital distribution, and the most competent platform to date, albeit it has its problems.
But didn't those publishers pay development costs? I've seen a lot of people comparing publishers and retailers (which is what app stores are) without understanding the differences.