All I'm seeing is a repeating of the same argument without evidence to back it up. Yes, the initial "just monitor the flow of magic through the Altdorf nexus" buy-in is easy. But scaling up isn't free; in fact, it gets exponentially more time-consuming and difficult to justify. Wizard-hours are not a plant that you grow, it's a limited resource that you can't easily make more of in any reasonable time frame.
We don't want tons of wizards getting involved in the existing leylines all over the place, because a lot of the wizards the Colleges have are either Journeymen--and are explicitly taught to not mess with Waystones except under specific circumstances--or Magisters who have much better things to do with their time than go around checking in on leylines and waystones that are going to be functioning just fine 99.99% of the time.
There is no "blazing a trail" here, because we can't pull in the manpower and resources of entire states into this, because the Colleges are the magical resources of the Empire and while it can spare wizard hours and resources for stuff like building permanent infrastructure, it cannot spare that for regular maintenance (which isn't even required) and monitoring of the entire damn network down to every leyline.
To paraphrase an early part of the quest: "I've got an army of thousands of peasants armed with crossbows and spears, and I've got ten cannon. You (the wizard) are the cannon. Find a way to make this work with thousands of peasants instead of the precious few cannon that I have, and I'll consider it."
The Colleges already work to generally check in on waystones they know the locations of and make sure they're still in working order. But this is not "every waystone gets checked and monitored every year", and the wizard-hours to measure energy flows for a substantial amount of time at each waystone don't exist. And as a reminder, the waystone network sends energy in packets of varying size and composition, making the process of gathering useful data even harder and more time-consuming. This is the kind of thing that can work if you have wizards with the right skills and tools placed at key waystone nexuses year-round to measure the flow through that, but getting more granular is just not practical at all.