Your goal looks doable; I've got a 4000 raw in the 240s going. It seems like you have to get the points quickly. This is a pretty poor map for a variety of reasons (though I had an insanely fast start), and I'd be pretty surprised if I can get to 12k in another 200 turns. That won't stop me from trying.
Early science focus looks like a bad idea on Epic, also. Learned that the hard way.
I started farm-spamming and expanding early, and it looked real good until around Turn 500. In retrospect, I should have conquered at least some of those 8 Maritime CSs instead of leaving them all as allies.
Here's something I learned the hard way, else I might have gotten 18K-18.5K instead of 17.9K:
Never, ever, use Modern Armor to "soften up" the last AI city in preparation for a quick take-down in case the score flat-lines. It tends to end the game prematurely.
I did a few things right, though:
1) I put a farm on every single tile that I could.
2) I completed the Patronage tree as early as I could.
3) I researched Fertilizer as quick as I could.
4) I conquered all the non-maritime CS (often using the very military units that I was gifted).
5) I put a work boat on every daggone fish tile.
6) I purchased granarys, aqueducts, hospitals, and medical labs whenever I could afford to.
7) I made extra settlers to be real sure that I had all available city locations covered. I even used 2 GAs to take strategic tiles from the last AI that allowed for the placement of the final two cities.
8) I kept a few Legions throughout the game to build roads so the workers could build farms.