I don't think there are one or two hard-and-fast rules on how to fix backroutes in general. It's specific to the level, the terrain layout, the number and type of skills provided.
I also struggle to understand your post in other ways.

Among others,
what do you mean by "enlighten the level"? Clear-physics mode?Buttons can force the player to visit certain locations in a level, much like pickup skills.
Pickup skills however additionally limit when a skill can be used (=not before you've visited location X), and are therefore better suited than buttons to enforce a specific order of events / skill assignments.
One-way arrows are a double-edged sword. Because while they limit the direction of destructive skills on the one hand, they can also provide hints from which side to approach an obstacle on the other hand - thereby actually making the level
easier than if the one-way arrows weren't there.
A similar thing happened to me with a
fire trap on a Lemmings: Hall of Fame level, where the trap being present would force you to dig at one point. Digging there is still necessary, in order to remove a chunk of terrain so that a Shimmier can continue through that section later on. But the fire trap made it obvious / inevitable to dig there, so I actually ended up removing the fire trap, in order to increase the entropy of the level.
The other thing with one-way arrows is that horizontal arrows are far less restrictive than vertical arrows. Because horizontal arrows can also be dug away from above, whereas vertical arrows can't be bashed away from either side. In other words, vertical arrows are "this direction only", whereas horizontal arrows allow all directions except the one opposing them.
The hint-giving aspect of one-way arrows can only be avoided whenever they are used as a fair version of manual steel. Meaning, you're not actually supposed to dig or bash through them in any way - they're merely trying to prevent you from going through chunks of terrain that can't be replaced by steel blocks (since steel often tends to be rectangular, and the level shape isn't always suitable for that). For the reasons just explained, whenever one-way arrows need to serve as pseudo-steel in this manner, vertical arrows are usually more effective, because they block more directions of destructive skills than horizontal arrows. But again, even that will depend on the level layout, and the skills provided.
It used to be the case that upward vertical arrows were the hardest to get through, but with the joint forces of Fencer and Laserer (especially the latter, since it can operate at a range) may have changed that.