Would you want to add a second Mandala (or something simular in function) to the Empires mod?
No, I wouldn't.
The thing is, each of the three content mods is supposed to FEEL different. The Mythology mod has a metric buttload of content (that's 1.2 English buttloads, for those of you who prefer the classical units), but it's all centered around that single screen, the Mandala, and the new yield, Favor. Everything revolves around your choices there, so you need to be in the habit of regularly checking that screen.
At the other extreme, the Alpha Centauri content focuses the units and buildings down to a relatively small number of chains, but has no central interface or mechanics at all (although I'd originally thought to have the ten extra policies use a SMAC-like Social Engineering interface); it adds no yields, but does add new resources.
The Empires mod is supposed to fall somewhere in between; I don't WANT it to all focus around a single Mandala-type system. Expanded diplomacy options might require their own interface, something that'll make it easier to tell at a glance what the power blocs are, but won't be some kind of diplomacy mini-game you have to play to do so. The Espionage system will also have its own interface screen, where you select what espionage actions to take, but I'm trying to design it such that you can simply ignore this aspect of the game if you want, setting all of your spies to defensive efforts if you want. Depending on exactly what goes into this mod, there might be a third interface window as well, but these'd be far less dominating than the Mandala was in its eras.
Also, remember that the Empires content is going to apply to all eras. There's not a clean Enlightenment-like cutoff at the end, and there's not a space-race-like initialization, so these extra windows will appear in all eras of the game. You won't need to USE the Diplomacy and Espionage windows much in the early game (when you haven't met everyone and don't have the resources to divert to spying) and in the post-spacerace Eras diplomacy is not going to be too effective as everyone's alliances are pretty much locked in at that point, but these are not the absolute cutoffs you see in the other mods.
I don't intend to have any sort of Alignment system for this mod; you'll naturally be moved into the various diplomatic groups by your in-game actions, but you won't have nearly as much control over that as you did your mythological alignments, where you could deliberately move yourself in one direction.
And finally, the Events for this mod are intended to be pretty much non-interactive. A Dark Age happens, affects all players equally, and will last for ten turns. There's no decision involved, no question of what action you take; it just happens, period. The unpredictability is a big part of the point of doing this; a human player won't be able to finely orchestrate some complex strategy (complete that national wonder that gives a free tech in 13 turns, because 12 turns from now you'll finish the current research) because you won't know when some event will come along and disrupt it. The goal of this mod is to change the underlying game experience in ways that breaks up some of the mid-era monotony in the core game, so I don't want things to be too predictable.
I MIGHT, on some of them, give you a couple options for how to deal with it, but it won't be anywhere close to the four alignment-based options of the Myth Events. It's more likely to be a 2-option setup where you decide whether or not to do something. Something like
"Civ X had a massive earthquake. Do you:
(A) send support (donate 100 gold and 10 food from every city, gain +100 relations)
(B) do nothing (-50 relations)"
or possibly a 3-outcome setup like Galactic Civilizations had where there's an inefficient middle outcome that directly falls between those two (donate 50 gold and 10 food from your capital, gain +25 relations). Part of the purpose of these events is to help break up the stasis where alliances have become so rigid that nothing can ever change, so quite a few of them will involve altering relationships.
That above event would be "paired" as well; maybe the game picks one civ to suffer the earthquake, with a random city losing 2 population, and the above choice is given to every OTHER civ at the same time. So if you were the one hit, you wouldn't make any choices, but you might get a massive amount of gold and food from other civs as they choose which outcome they prefer. Depending on how many civs donate, you might actually come out ahead on the deal, food-wise, and any relationship changes work both ways.
Now, some of this I can implement before the DLL, and once the Mythology mod's a bit more stable I'll probably do so. Hopefully, once I have something in place it'll be easier to illustrate my points.