The main concern isn’t about the extra mid-slot, but the lose of a low-slot to get it.
Being an armour tanking faction the lose of a low-slot is a major loose. Many believe a high-slot would have been the better option to sacrifice for the mid-slot.
As for tracking there is the low-slot tracking enhancer that increases not only tracking speed, but also optimal range.
But it’s been noted the precursor ships are naval factor ships, though have not the best EHP when comparing to other naval faction ship of the same class. The mid-Slot is an issue for the frigate and battleship. Though as to how to address this is questionable, though a few ideas have been floated in `blog-triglavian-technology-ships-weapons