I just finally finished reading through this topic. Seeing how other games play out is fascinating. I almost find it absurd Li-halan somehow has cities on Nowhere, and I'm surprised people have so little interest in De Moley, one of the most important planets in the game. You can harvest a lot of trace from every single hex on these barren worlds (including Daishin). Granted, it isn't easy to take, but certainly more than worth it. Not to mention it actually has a League agora on it. It's supposed to be a Brother Battle planet lore-wise (church faction), but obviously having Decados go to war with the church over an expansion planet would've hurt balance.
As far as proscribed tech, the Nova creators took it out because when the church proscribed a tech, a bug in the game unproscribes it when you close out the game, even if you save. It's a shame, because it was a great mechanic. Church sects are bugged although one can argue they still can play a role. For example, suppose I gain control of a church on someone's planet, with very few troops of my own. Suppose those troops are all orthodox. I change it to avesti, they all lose 5% loyalty, now they are easier to route. Now I change it to another non-orthodox sect, and they lose another 5% loyalty. As you can see, I can do this several times in the same turn and make all of their units 0% loyalty. Likewise, if I had been producing avesti troops elsewhere (by changing that planet's sect to avesti), and made this change, they would gain 5% loyalty. As you can see, this could bring units up to 100% loyalty, defeating the purpose of officers. If you start producing units of other sects for long enough, you can see the value of these sects in the church diplomacy screen. When the church appoints a new patriarch, it's of whichever sect has the highest value (which is always orthodox unless you mess with the sects). This of course serves no known purpose but it's pretty cool to actually have an avesti patriarch instead of orthodox. It just goes to show EFS had many promising ideas that never were implemented. I have this dream where I'll someday reprogram EFS with all its original goals in mind.
When the league declares the third republic, they just declare war on everyone. I think you can actually still purchase resources. They really won't pose any military threat by this point, and cannot declare themselves emperor or anything like that. You can modify the number of firebirds this happens at if you want them to essentially be a trading partner the entire game.
And as for in game messages, you can actually send as many as you want in one turn. There is a character limit to how much the opposing player will see, so some gets off if you don't cut it off somewhat early. I always liked using this method ofcommunication since it was in-game and included their portraits.
As for an interesting tidbit of information, Holistic Design actually did advertise this game. I recall seeing ads for it in Gamepro (or was it PC Gamer? I can't remember), and these ads had Winston Churchill in them for some reason. Seeing the miniature screenshots of it sold me on the game and I played it constantly for a few years. Holistic was developing Noble Armada, a 3D space combat/trade/exploration game set in the same setting, but that never went through and they seem to be a dead company at this point. It's a shame.
Firebirds do eventually become fairly useless. I've been trying to mess around rebalancing the original EFS 1.4 to make them a permanent resource to consider, and return to the pre-combined arms combat (in combined arms, direct/close hit both tread and foot units, when before it was direct fire hits tread and close hits foot units). I always liked that added dynamic, and I think I've found a way to circumvent what caused combined-arms in the first place (people weren't making combined stacks of tread/foot because of it).
If you think the game is buggy now, just try playing it again straight from the box, version 1.0. The bugs are overwhelming.
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