My only hesitation about 1N of horses is that you'd then have two cities 1 tile from the coast. And we all get

when the AI settles like that so that we have to raze and rebuild. I guess here we're trading long-term and short-term: Getting the horses online ASAP vs. having better cities later. Here's my (first, be gentle) stab at a dotmap, taking a more long-term view:
Red could be settled now, getting horses, silk, and low distance costs. It would need a border pop, but then, so would the desert tile.
The purpose for Red's spot not being 1 more W is to allow blue - fish, corn, horses, 3 grassland, 5 coast, coastal. The rest of the land isn't great, but the

can turn the food from the fish and corn into hammers. Meanwhile, the second border pop (if red isn't already there) would give you control of the peninsula, which might be a big advantage later.
Yellow could then be settled once you have iron working, to claim marble, gems, and dye.
As I mentioned, this is my first ever stab at dotmapping from scratch, so take it with a grain of salt. Also, obviously, things could change drastically with BW, IW, and further exploration.