Cows before rice gives you a big production advantage, plus the extra turn worth of yield. The real dilemma is whether to dick around trying to settle your horse city to get the sheep, so you then have to tech mysticism and build a monument there and wait around for your immortals, which probably means you need at least a couple warriors in the meantime. On Deity I vote for not dicking around. 1NW of the horses, dont waste your time on mysticism and a monument, get your immortals asap, save time and beakers and hammers, still have a useful city even though itll suck in the later game. It can work four cottages for the capital and can at least farm the one riverside grassland once it turns the FP over to the capital for the bureau boost.
Self teching archery as Darius with nearby horses revealed would be pretty...unusual. To put it politely.
I would go wheel->mining->BW->pottery->writing. Don't waste a single turn teching something unneccessary. I'd prioritize BW just because you need 3+ quick immortals once horses are hooked up, and you have too much food and not enough production for that. You'll want to whip workers and settlers into immortals until you have sufficient fogbusting. Sufficient fogbusting with Darius really means just protecting your cities, not neccessarily fogbusting every city site you want. Barb cities are kind of a good thing as long as they're not on hills, flanking II immortals eat barb cities. When you no longer have a pressing need for barb defense you can pump settlers and workers in your capital at size 5 working rice+cows+gold+FP cottage+oasis (because your horse city should be working the second FP cottage). All those high yield tiles makes whipping counterproductive for the expansion phase.
Edit: size 6 with the gold happiness, I suppose you'd wantto mine the grassland hill or get an early start on another cottage if you find yourself growing to size 6 before pumping out settlers and workers. Maybe grow on a granary...but then again with whipping not being optimal in the capital there's no reason to build a granary until you actually need the health.