My personal take: Tunnel Goons is defined by its straightforward action roll resolution. For better or worse, it's characterized by pass/fail zero-sum terms.
Degrees of Success only matters when chopping away additional HP. But it doesn't add narrative flourish the way it would in, say, FATE.
Other hacks may change how inventory is handled, or add a secondary risk factor (aside from losing HP) but the 2d6 + bonuses is always there.
By introducing Gambles, Stunts, and Advantage Dice, it fits the genre 100%, and creates a more distinct play experience. But it also deviates fundamentally from the core simplicity of Tunnel Goons rule set.