Conclave - 5/4/3

Fortress - 5/4/3

Town - 5/4/3

You did say ideal, right?

I'll usually take anything with 2 essence over a better Grain/Materials (so say a 3/2/2 over a 4/2/1) because the essence is so flexible. Enchanted hammers for the win.

conclave more essence.

town more production, same as fortress.

My ideal fortress is would be something like 3,4 or 5 Grain with 4 Materials and 2 essence or more.  Which is usually like a forest near river tiles and a resource or two nearby.  Rare.  But it happens.

Towns I usually make out of anything. 

I usually have at least one of my Conclave high grain if I can.   If you do 3 or 2 grain you'll have much harder time getting to level 3 and 4 city. 

Non-ideal.  I'll usually make any 3+ material town my first fortress.

This.

If your AI neighbors have already made their capitals into conclaves, find the tile with the highest essence, go for cash income, and rush everything, including troops. 

What foul sorcery is this?

Dense resources?

Between tiles with non equal totals go for the higher one. (aka, 3+3+3 = 9. 2+4+0 = 6. 9 is better than 6). But when equal prioritize Essence > Materials > Grain

Different builds need resources to a different extend. 

Wealthy sovereigns can just rush stuff from their capital and look for a much better second/third city.

Adventurers can rush one pioneer as well, so they can get a second chance, and rely a lot on heroes.

Enchanters get an extra essence from the scrying pool.

Earth mages can turn one essence into one material when they need to.

Bandit Lords and Beastlords (as you pointed out) can get their troops elsewhere.

But I think that someone who is NOT playing one of the above builds really cannot overestimate the materials of their starting tile.

When I play on ridiculous, I often play a wealthy adventurer with Enchanters and Earth magic, and I STILL hope for good resources.  But I do not need to re-roll if I am unlucky.

Last I checked, you rarely have only 1 spot you can settle. So its your choice what resources you prioritize. A 3x3 array is 9 spots with 9 different sets of resources.

Getting high material (bonus if near woods, less important river) gives you immediate out of the box better city. Grain takes 50+ turns to start to matter. Essence can matter right away with the right spells.

That immediate bonus from materials gives you the ability to pioneer spam. It also gives you the ability to building spam. 4 mat city builds buildings 2x as fast as a 2 mat city. That is huge. Only thing population gives is gold. buildings give research, production, gold, mana, and more. And they give it faster.

A valid strategy. Although you are likely to get earth 1 later on via a champion or if you choose enchanters, book. Early on all I have on cities is meditation. A dozen cities with meditation gives you a heft mana supply really early on which can make quite a big difference.

This makes essence MORE important. A 4 essence city +1 from pool +1 from conclave... you got 6 essence. Thats +150% grain, +1 mats from enchanted hammer, +6 mana, +6 research, +6 gold, +some other enchantment... then buildings give you impressive bonuses, including -30% unrest, +6 mana, and +6 material (alchemist)

You are generally correct that essence trumps materials, but I sometimes deviate from that rule for my first city.

Nowadays, I play mostly Emperors with Death and Water, and Kings with Earth and Water.

Emperors will take a x/4/1 before a x/3/2, and Kings will take a x/4/2 before a x/3/3 for their first city (and only their first city)

They both cast "Inspiration", and the Kings also cast "Enchanted hammers". "Mediation" is a nice bonus, but not essential for the first city, mostly because I do not need the mana early on.

Basically, I prioritize "Inspiration", because it doubles research, and then I want as much production as I can get.  For additional cities, usually essence is more important, but once again, there are exceptions.  It's just that by taking cities from the AI, I can get great essence, and those make perfect conclaves and fortresses, but for towns, I find that cities settled by me next to river/forest work better.