Incidentally, I've upgraded my desktop computer to a 1600x1200 monitor, finally replacing the 1024x768 CRT that I used forever. Naturally, this makes Civilization screenshots very big. I would rather not resize them all narrowly, since that shrinks the text to unreadability. I think a good compromise is to give you that button above which will automatically compress images to your window, if your browser doesn't already have the capability to do that. (Refresh the page to undo it.)
Anyway, there's a fantastic start. Double gems, plains hill, four flood plains in range plus more northward, freshwater rice, and even ivory close by. I've found that the happy cap is extremely confining such that some Mining or Hunting resources are essential; having that extra happy headroom for a couple more cottages makes a big difference on getting to Currency and Calendar much faster. Seriously, I had even tried and rejected a few starts with five or six food resources, because they just couldn't research fast enough on a tight happy cap. I wasn't start-whoring for gems specifically, gold was also acceptable, but one or the other was mandatory.
Naturally the first research was Mining, but then I went for Wheel - Pottery before Bronze. I want floodie cottages up ASAP.
The one downside of Darius of Persia is the dreaded scout start. No worker steals on turn five, you have to build your own warrior. I've become convinced that the right thing to do is build warriors at max hammers ASAP. You'll recover the food opportunity cost by getting a stolen worker farming sooner. (If you don't, throw away the map and try again.) With 4 hammers from the plains hill and forest, the first warrior emerged on turn 8.
My first worker steal came on turn 19 from Victoria, plenty good enough. But she wouldn't make peace. I am pretty sure the AI's willingness to make peace in these situations depends heavily on the power rating of both civs. Presently I made the situation worse when my warrior attacked an English scout but lost. It took quite a number of turns, after killing a different English scout and researching The Wheel for the power increase to finally force peace.
My scout had discovered France way down south, so the second warrior headed there for another worker steal! De Gaulle made peace right away without trouble.
The first warrior continued from England north, and found America. He skulked around for a good twenty turns until the worker appeared -- notice that all of Washington's food needs Animal Husbandry. But it did, and we stole it. Washington signed peace right away too. (Man, how arrogant is this guy, naming his capital city after himself! Who does that? 
)
By now Persepolis had built a few more warriors. One wandered over this way to Babylon for a fourth steal, and Hammurabi also signed easy peace.
Back to England for round two. This was almost a nasty mistake, England went a long time without taking peace again. I had to comically track down two more English scouts all over the place -- and couldn't risk hitting them on defensive terrain. But killing both of them led Victoria to peace finally, about thirty turns later.
So that was five workers by turn 60, well more than enough to get a quick start on development. I didn't get any more for a while. France went forever without building a second worker. The espionage screen reveals that: watch the hammer count in a city via Sabotage Production, to see if it's building something fast enough that it must be taking foodhammers. I kept close tabs on that, only to see Paris only ever put one hammer per turn into things which could never be a worker.
In the shot above you can see the development of Persepolis. All the stolen workers had arrived home and improved the rice and both gems very quickly. The commerce from the gems sped me towards Pottery and some very early cottages. The snowball has started. The only thing for Persepolis to build at the moment was the barracks, but that's fine and will help the Immortal rush. It would get paused to build the granary once Pottery was reached.
Some quiet time followed. I researched Bronze Working and Animal Husbandry by turn 100. Here's the important moment, are there horses reachable anywhere...
Yes! Although in a rather food-starved location. The best spot was 1E of the horses, bringing in two choppable forests and a floodie for later. Persepolis whipped the settler for that immediately.
Writing followed, researching very nicely with the double gems and several floodie cottages. Persepolis regrew to size 6, but was under both happy and health trouble, so triple-whipped the library.
The horses quickly got improved and connected, and all the stolen workers started chopping like mad. (Every forest chop was 60 hammers for exactly one immortal, easy to micromanage.) Persepolis also whipped one and overflowed onto more. Here we go.
Turn 126, 2240 BC, seven immortals advanced on London. Two archers on defense to begin, plus an expected third whipped. I even won one low-odds fight, so we took the city at the cost of just two immortals. Nice! Nottingham also fell. Vicky still had two jungle cities, which weren't worth spending immortals on now, so I just settled for peace.
The other reason to leave Vicky alone was an extremely urgent situation over here. Babylon had copper in the city radius.. that wasn't hooked up yet... because he lacked Bronze Working and WASN'T IN SLAVERY! I built one more immortal from each home city and chopped two from London, replenishing the stack to nine strong, should be enough to take out even three archers on that hill. And so it came to pass, with one immortal even winning at a ridiculous 8% odds! Babylon was a really good city too: rice, gold, copper, pig (under the combat log), forests, river.
Next target Washington. Two archers on defense and whipped a third, but we won losing only two immortals.
Next target Germany, way up north, who super conveniently had built Stonehenge for me! I conquered Hamburg too. Then I let Frederick live with his last city. It was on a hill in a bad location, so no sense throwing immortals away at it. I kept needing to remember that I wasn't on a mission to wipe out civilizations; the purpose of all this conquering was to acquire good land for myself. All these capitals had bunches of food and were well worth keeping, but other cities would just crash my economy.
Next target, by now pretty much just because I can, Lisbon. Combat II immortals attack fortified archers with about 62% odds, and if they survive quickly become Combat III also. I made peace and left Guimaraes alone for the moment - it had three archers and no food and I didn't need to throw away immortals on that.
Next target, Bibracte. I waited up for a few reinforcement immortals, since the land layout meant my army had to walk several turns through Celtic territory giving him time to whip defenders. And indeed there were five archers on hand, plus walls. A bit bloody but we captured another quality city here.
I ate Brennus down to one city, but once again didn't want to waste immortals against three archers for a raze-doomed city. But here's a nice way to get my dirty work done for me. Free mutual struggle merits too.
Six capitals conquered by 1500 BC. Not quite as fast as quechua rushing, but much more reliable, the rush isn't doomed if the AI gets a single axeman. Spears were a concern, but the fast immortals could reach and disconnect copper quickly if necessary. Whew. Anyway, now it's time to talk about economic development.