Consider this:
So, I understand that, at some point, the idea is that, due to differences in timescale, 1 species evolving to the next stage, say from Macroscopic to Aware, would lock other creatures out of being able to make that jump. However, given that Animals, Plants, and Fungi all evolved to macroscopic separately, and the sheer number of times life evolved to multicellular, I would like to propose that the transition from microbes to multicellular to macroscopic be handled a little differently than later stages will be.
First, I believe that the timescale difference for microscopic and multicellular should be reconsidered/removed, and that perhaps there should not be a limit on the amount of microscopic organisms that can become multicellular, or, perhaps, there should be a large number of available “lineage” slots to compete for. Putting aside weather or not my suggestions for AI and Time Limit Difficulty Settings gets used, it makes little sense to have the first creature to reach Multicellular lock others from reaching it when so many groups evolved to Multicellular multiple times, and it especially doesn’t make sense for a plant reaching Multicellular to make it so that animals can’t evolve.
Second, I think that when the transition from Multicellular to Macroscopic occurs, different trophs/miches should each become the progenitor of different Macroscopic Trophic Lineages. To use Earth as an example, there could be 2 Photosynthesis Lineages (Green Algae and Land Plants) and 2 Heterotroph Lineages (Fungi (digest food outside there body) and Animals (digest food inside there body)) (this is, of course, until in some distant future someone implements a difference between red, brown, and green photosynthesis and we need more lineages). To be fair to life and the possibilities of Thrive, each troph could have its own Trophic Lineage slot or two (the differences in how Fungi and Animals digest things could be considered different trophs (Fungi’s form of heterotrophy is also called being lysotrophic or saprotrophic), with something like “Energy Production” being a possible roadblock that prevents less effective Multicellular organisms being able to fill there potential Macroscopic slot/s (that is the reason against Plant Civs right?).
Basically, at the time the player, or on harder AI difficulty settings the first species within their “Trophic Lineage”, first makes the transition to Macroscopic, every Lineage of Multicellular organisms could be checked to see if they have a potential candidate or two, too also transition to Macroscopic as the progenitors or their respective new Macroscopic Trophic Lineages. It would be expected that many potential Lineages would not have a worthy candidate, though potentially they could in some games depending on how that particular game went.
One thing of note, depending on how many Trophic Lineage slots were available, it would be a good idea to take measures against a multitroph taking multiple Trophic Lineage slots. That would defeat the purpose and also likely cause problems further down the line when they were less likely to be able to Awaken. One possible suggestion would be to have a “priority list”, from least likely to succeed to most, and check the multitroph for the highest priority not yet filled, specifically plugging that Lineage and leaving the others open to worthy specialists. Alternatively, you could just make slots for every combination a Single, Double, Triple, Quadruple, Quintuple, or Sextuple troph possible, but . . . I think just assigning a multitroph one Trophic Lineage and ensuring it is not in multiple slots would be easier. I would recommend Photosynthesizers be second group from the bottom (so if there is a Photothermochemotroph it will not block the more likely to succeed pure Phototroph) and Heterotrophs last (so a Photoheterotroph does not lock them out).