Should T3 Mass Fabricators Be More Efficient Than T2?

Just as higher tier engineers were adjusted to be more efficient in build power, higher tier mass fabricators should also be more efficient for mass generation, especially given the unit cap.

There are a lot of downsides to this idea. For example, such a change would kill off second layer ringing T3 mexes with T2 mass fabs, an important part of making late game raiding more impactful. However, I feel that the benefits of not eating up unit cap outweigh these concerns.

To be clear, I am not talking about the unit cap from just 2nd ringing T3 mexes, but from late game mass income expansion, where it is most mass efficient to simply spam T2 mass fabs. The only real limiting factor, aside from unit cap, is space.

A strong argument for this change is consistency.
It doesn't make much intuitive sense that a T2 mass fab would be more efficient than a T3, and by a noticeable margin, too. Of course, it is not quite as simple as comparing raw mass cost and energy draw to mass generation. Space is a factor, for instance, but generally, T2 mass fabs are superior to T3.

It also fits with the progression of the game. You’ll always upgrade your mexes to T3 before turning to mass fabricators, and if you're at the T3 mex stage, you’ve almost certainly gotten to T3 engineers and can build T3 mass fabs.
With T2 mass fabs you gain access to them well before you want them, and by the time you want them, you've likely already gained access to T3 mass fabs.

The more I think about it, the less sense T2 mass fabs make when T3 mass fabs already fit into the game so well. This change would probably make T2 mass fabs almost entirely obsolete, but I don’t see that as a significant problem.

Eco Compendium by Cheeseberry

I don't think T2 fabs are far more efficient:

• For eco efficiency: T2 mass fabs have the same efficiency as T3 fab grids unless they're placed without shields adjacent to T3 pgens, a template which is very vulnerable to random bombers/arty/novax/tele and not dense at all.
• For space efficiency, T3 fabs win by a long shot (1.77x denser, and cleaner templates with pgen adjacency). This also means they are way easier to shield, with high HP on top of that.
• For adjacency efficiency, T3 fabs are great next to 2xT3 factories and T2 fabs are great on mex, with roughly equal payback time efficiency. T2 fabs on mex are more common because it's a lower investment cost and factories fit for t3 fab adjacency are rarer than mex with storage.

The differences in payback time are in a matter of seconds so I don't think there is a clear winner for which is better to eco with since the remaining differences are about T3 fab durability vs T2 fab low cost/unit (easier to build a small amount of and start paying back a little quicker).

For the other non-eco points:

• I don't think there is a big "consistency" issue with T2 fabs being T2. Lower tech units/structures are often cheaper and more efficient but less dense, and that doesn't mean they become completely obsolete when higher tech appears. Some examples: T1/T2 PD, T2 shields, T1 arty, T1 air scouts, T1 engineers, navy, T1 bombers, T2 gunships, mex upgrades, T3 units (compared to T4s), flak. T2 fabs fit into this pattern just fine.
• Making T2 fabs obsolete would be lame and taking out a dimension in how people can eco. Plain downgrade in gameplay.