To make up for just how big the units/structures that t3 can make, and how there's a cost to build rate ratio inefficiency, how about increasing their build range to something similar to the ACU's build range? SCU too, if it's not already? Maybe increase the range of ACU build range with t3 build suite by a little bit too.
Without this range, it's super annoying to assist it to build stuff like experimentals and even walk it away from the factory if other engineers are assisting it, especially if they have to reclaim something to build in that spot. Also eases the ability to build exp in the water from the shore line. Makes it handy for making extra large units like CZAR, Tempest, T4 bomber, etc.