Essence isn't optional it's downright mandatory. To top it off, a city with no essence means no city enchants. It's that important. You can't even cast.
This is the first build I even remembered to use city buffs, except on my one military production city, which was almost never my starting city. Theyre powerful and useful, but I fail to see how they're mandatory. A good solid production city within spitting distance of some shards was good enough before. It's good enough now to get started.
Like I said, you're competing against the AI, which only seldom utilizes an essence source. So that's a big advantage over your opponents. So it's great if you roll one to start with. And if I see one out in the world, I'm going to grab it. But mandatory? Hardly. Obviously a 2 essence city would provide you with the potential for a number of bonuses, but I have yet to hear a compelling argument why anyone would be gimped with a 3/4/0, or a 4/4/0 starting city.
I'm not arguing against it. I havent fully formed my opinion yet. I'm just not certain I see the case for essence as a gimme. It seems like a luxury to me. I think people are just sort of used to the idea that theyre supposed to be able to cast as many buffs on any city they want, and clearly that has changed. Now they are more like slotted magic items you find, with the city spells being the "gems" you can insert to it to customize it with magical bonuses to suit your wishes.