Victory! I got the announcement when the computer finished running turn 117. I was surprised, because the Aquilaeans and Tessellate still had nearly 250 colonies between them.
That turn I captured nearly a dozen enemy colonies, but I suspect it was the fleet action in Tyrik that tipped the balance. The large Tessellate fleet I mentioned in my last post moved into Tyrik, one jump from Resshrak (scene of the last big battle on turn 103). I gathered five fleets (65 ships total) and a number of sats to defend the most valuable colony in the system, but the enemy chose instead to re-capture the adjacent planet. So on turn 117 I sent all 5 fleets to attack the 129 Tessellate ships (almost all CR, and almost all armed only with planetary napalm).
Some of our ships started out intermingled, and six of mine spent most of the battle completely surrounded. Whenever possible the Tessellate closed to 1-square range, but the only ramming I saw was when 4 CR rammed one of my battleships (it survived with 68% damage). Otherwise it was a slaughter: 129 Tessellate ships destroyed vs. 1 Terran battleship damaged.
A few sectors away, another Tyrik colony with several captured shrines was threatened by a 15-ship Tessellate fleet. Wanting to save the shrines, I dumped thirty-odd sats backed up by a battleship and three battlecruisers. Unfortunately ten of the Tessellate were Talisman-equipped battlecruisers with shield depleters and shard cannons. Worse, my sats were out of position, and worse still, the enemy got the first shot. Fortunately my ships knocked off several Tessellate and lasted long enough to lure the enemy into my sats. The planet and all four ships survived, the latter with only one component each.
On top of that, having burned through Tessellate counter-intel the previous turn, I captured three Talisman battlecruisers via crew insurrection. All in all the Tessellate lost over 150 ships in that turn.
Final score was Terrans 6.1 million, Tessellate 1.4 million, Aquilaeians 0.7 million. The Narn and Pyrochette had two colonies each, and the United Flora had been completely liberated.
This was quite an exciting game in the early stages, but it appears that even at five to one odds with a small bonus and no mines, the human player still has the edge. I'm thinking of going again but with everyone breathing the same air; I gained a major advantage by matching captured populations with the proper atmosphere. I like expensive tech but I hate the Talisman; I may mod the Talisman down to a super combat sensor (e.g. 100-120% accuracy, but subject to ECM, etc.).
Or I may wait for SE V.