Well, first, I'm not quite sure that Steven is NFL material as a DL. In my opinion, based on his body of work so far at the NT position, best he can probably hope for is a late round slot or undrafted free agency. Assuming that he ends up with a killer junior year, and the talk being that he's roughly a 3rd - 5th round pick, I'd probably advise him to give it a shot, take the paycheck, play the 2-3 years he'd probably last, live CHEAPLY, then go back and finish his undergrad and graduate degree.
As far as an equitable solution for the player and the school; the way things are now is probably the best it's going to get. Forcing a kid to play all four years, or in a bowl game, is, as far as I'm concerned, akin to enlisting in the military, or indentured servitude. Neither would be appealing. Kids should be free to take a shot at the NFL and succeed (or fail), and the schools ( at least the P5s) are going to get a check from whatever bowl, regardless of whether the star player is there.