Another radical idea for FE- change to mana and how it's used

I do like the first idea here. One of the benefits of having a percentage decay, is that with a given mana income, your pool with soft cap at some number.

With a 5% decay rate (for example, the numbers don't really mean anything outside the context of spell costs), and 10 income, your mana pool will level off at 200, when decay = income. One of the nice things about this system is that it fixes the problem of having a long period of peacetime, where you can accumulate enough mana to make casting even high-level spells pretty much trivial.

The rest of your ideas I think are thoughtful, but not to my taste, personally. I was very pro-casting points at first, but after playing 1.1 a bit, I'm much more ambivalent.

So... yeah, I would very much like to see a moddable decay rate in the game.

The second AI is more to help the AI out, by getting rid of the decision of whether to blow mana or not in tactical/quick battles.  Right now the AI will not use mana in quick battles at all, though it did in the betas.

Rather than even a soft cap on mana accumulation, I'd prefer to see the Enchantress magic system rich enough to make hoarding at least part of a viable strategy. The game needs strategic spells that take multiple turns to cast, with variable mana inputs that affect results and casting time. Things like item forging or attempting to dispel another sovereigns strategic spell.

A small mana bleed per turn would not limit big spells as badly as you'd think, especially since casting the spells would reduce the bleed.

I don't see how my suggestion would make what you are trying to do unviable.

Worst case- you lower the mana needed slightly for the biggest spells.  Problem solved.

Not exactly. What I'm hoping for is at least a handful of spells with open-ended mana costs, such that in certain sorts of late games you need to make decisions about whether to stockpile mana for reasons like: needing to recast a big spell quickly because it got dispelled, wanting to forge a Truly Ridiculous magic item, or wanting to be nearly certain that your attempt to disrupt another sovereign's big overland spell works.

For me, the game currently lacks any interesting tradeoffs when it comes to the magic system. I want unlimited mana accumulation because I want me & the AIs to have to consider when or if we stockpile and what to do if can detect that a rival is stockpiling heavily.

Where is mana held in the game? Is it in the Soveirgn? It is certainly taken out of the Crystals. So then where is it being stored? I think it would be interesting to have buildings that hold mana. That way there could be a decay rate and a trade off between money and mana, assuming maintenance for these magical repositories is rather high.

What say you?

That's one of the Big Questions that's not yet been answered because content was a second-class citizen through the beta and  released versions so far (Enchantress looks like it will take a different approach...).

As the apparent Lone Defender of the Dearly Departed Essence Mechanics, I'd prefer to see mana as held by the sovereign. Imbued champions would be magically linked to their sovereign and the mana they could spend would flow through that connection, preferably at a rate determined by their restored Essence stats, and they might or might not also serve as mana sources for the sovereign.

Mana-related buildings other than shard shrines could be fun, as production boosters or support for imbued champions. The cap thing (hard or soft) just strikes me as a short-game/RTS perspective that I'd rather not see in an 'epic' TBS. A mana bank building just sounds cheesy (or at the very least kind of un-magical), unless it is perhaps at the heart of a sovereign's capital, not buildable, and not affected by the mundane economy. Could be fun to have different outcomes to conquering a capital depending on whether the attacker is prepared to deal with a massive mana release from the conquered mana storage structure. But even that would probably not be so much fun for me.

Ooh!

The mana could be stored in statues that come to life to defend the capital. Now that would be epic. The more mana it has, the more powerful its spells are and it loses mana for each one cast. The temples that hold these sentries could be built instantly in the capital and only at level 5 for any other city. If one is destroyed, it might explode with what mana is left, devastating the map once again.

I realize that is unmoddable and very unlikely to be considered for any version of Elemental, but would that be cool?

I see what you mean about preserving epic in the game, though, and I agree that all we really need for WoM is reasons to make strategic decisions. Like saving up during peace time or converting mana to gold or even enchanting one's economy. During war time the choice should be about which battle to use magic to turn the odds in one's favor. On a strategic level, it should get much more complicated. There are monsters to summon, unit improvements, mana regeneration rate, and there should be something like buffs and debuffs for a single season. I very much enjoy Disciples for the magical ways of tipping the scales slightly in one's favor.