Are we sure the torians not having a capital is not a bug.
I actually think, that it isn't. The Arcean, Torian and Snathi tech trees in general feel more bold and diverse, which I like. Note also, that instead they have +% research on all the techs were you get buildings, that is part of why I conclude that they are supposed to be a pop centered civ. What concerns me more about the Torians is them not having the foot distribution (+% food), which I would have expected on a pop-centered civ.
I am currently giving the synthetic play style a second chance and them having no capitals at all i spuzzling me more, because the way I read that style, it is supposed to be centered around one or a few colonies at the start and then invasions instead of big colony rush. But at this point I had little exposure, so don't read too much into it
A nice tech tree fix to equal the thslans for the others is to give power plants a bonus to raw production not total manufacturing to the power plants.
Even considering, that hives and gaia were changed to give plus manufacturing instead of plus raw production recently? Some more rambling about this: The Thalans have a malus to growth, the original intend of hives might have been to make up for a lower population. Why not change the tech tree to actually reflect this (remove last tier of farms or so...) instead of hives?