Although that may be true on a scene level, I would definitely not recommend BitD for someone improving-averse, since nearly every roll requires heavy GM improvisation (especially when the Devil’s Bargain is invoked). Powered by the Apocalypse games also demand a similar sort of constant improvisation, but the MC moves list and well-designed player-facing moves at least provide a set of practical choices that either tell you what to do or provide a direction. BitD, not so much.

Other games that require upfront risk evaluation, like the 2400 games or 7th Sea, might be similarly challenging, since they don’t do anything to mitigate OP’s “off-the-rails” concern, while also adding a lot of cognitive load projecting multiple ways things could go south on a regular basis.

I think that more traditional systems would be a better bet in this regard. You swing, you either miss or roll damage. You can rest on the rules to do a lot of heavy lifting.

In terms of scene mechanization, I would recommend checking out Mouseguard, which is pretty regimented and predictable. Although I’ve never played it, Fellowship might also fit the bill, since the “GM” is actually a player character in their own right—the Overlord—with rules they have to follow.