I am pro-wall, and I think reducing the required enforcement coverage will make the corridors easier to police, as well as freeing up resources at the ports of entry.
Read this carefully
IT WON'T WORK
Walls by themselves DO NOT WORK. In order for walls to work, they must be heavily guarded and patrolled throughout their entire length, otherwise people will go around them (by swimming or boating) over them (by microlight) or under them (by tunnelling). There are numerous recorded incidences of all of the above. There are also recorded instances of drug smugglers using drones to get drugs over the border. They may even go through the wall (a power diamond concrete/steel cutter in a remote location). Therefore, rather than
"freeing up resources" they will actually take more resources. The drugs will still get in through tunnels and through ports of entry and via the Gulf of Mexico in boats and drug submarines.
However, if you take that $5-8 billion Trump wants for his white elephant vanity project, you could build a gold-plated, state-of-the-art electronic frontier with, hidden sensors and observation posts covering every inch of the border, even in places where building a wall is physically impossible.
Do you know how I know this will work? Its because it already has, right there in the USA. There are two places protected by just such electronic frontiers - Area 51 and Dugway Proving grounds. In over 50 years, very few people, if any have ever been able to get into them, and those that have were caught almost immediately.
The addition of surveillance drones to a US Mexico electronic frontier would make it even more secure.