I can't check the save just now, but some preliminary thoughts.
Case Départ
Can you improve the last Grassland Cottage in Case Départ one turn sooner? If we work this instead of the Marble @ size 9, this would let us grow to size 11 on T82.
It's possible if I use all 3 Workers around Case Depart (@T76: Silk Worker cott 1/4, PH Worker moves 2N1W farms 4/5 & cancels; @T77: 3 workers are on the GL and improve Cott). It might or might not delay Farm for Rice Pudding depending on if I send 1 or 2 Workers there.
Duckweed suggests that if we build HE here we work Marble though.
Looking at your screenshot, with +3GPT, suggests that we will need the Heroic Epic to fund the next tech. Perhaps build this for fail gold, and only bother with the Market on those turns that another city can build the HE too.
Yes it might be best, especially if we keep my current Rice Puddingg micro where I have produced 2 Miss and a CH by T81 and can switch to actually start building the HE on T81.
Rice Pudding
If you build a Missionary and put the OF to a Missionary, will this speed the CH in Golden Sands or Cornish Cow?
This would also mean that we don't need to whip the city, which is food poor, twice. We could chop the Courthouse as soon as Mathematics is in, or choose to whip again (working more improved tiles in the interim).
I tried this and it just felt really slow. I agree the city needs to grow but we have mandatory builds we need to complete as fast as possible.
Producing 2 Missionaries and 1 CH in 4 turns and still end up @size 5 is pretty decent I think. The city can take 2 whips IMO and I'm not whipping away cottages, so the early CH will snowball much better on the economy than growing on GL Mines (I think). My micro delays the 2nd Missionary by 2 turns in Cornish Cow which is still before we whip the CH there so I think it's a good compromise.
The first Missionary going to Golden Sands and a chop allows Golden Sands to 2-pop whip the CH on T81 which I like because 3-pop whipping that city is a bit harsh compared to food surplus (plus it's the earliest we can do I think).
Sheepish
Could you whip the Missionary here @ size 5/6 into the Courthouse? This would mean that Constantinople needs to build one less.
I guess it would be possible but I actually think it's not that bad to 2-pop whip another Missionary in Constantinople because we can OF in CH (food is definitely not a problem in this city and until we clear all that forest there aren't much interesting tiles to work). Not sure about this (I don't think my micro really delays the CH in Const).
The Missionary would go to Stone/Dye, which will not need religion until it whips its Granary (~T85).
Religion is also important for border pop, we might want to get our hands on the Stone sooner rather than later (possibly).
Constantinople
It looks like you are trying to slow growth with the Plains Hill. My inclination would be to grow faster and whip more quickly. Then use a 3-pop whip of a Courthouse to keep unhappiness in check.
The Plains Hill is not the best improvement for 4 Worker turns, unless you need the extra

to complete something specific. Otherwise, Workers moving from East <----> West can improve it later on, when they are in transit.
No I only work the plains for 1 turn because it yields 2C and allows not too many hammers in Missionary for a 2-pop whip on T81. I'll try out your suggestion though.
You're right about Worker turns in that area, I was uncomfortable with this because the disposition is awkward. I need to keep these 2 Workers in the area because they have to be ready to improve Thess Rice after its border pop. I'll try something else with your suggestions (including those you edited below after looking at the save).
Thessalonica
How much

on the turn that the Granary completes?
Very good question, I didn't pay too much attention to whip optim in this city (I just work the FGH for the 1 turn @size 2 and then whip, maybe I can wait 1 more turn for a better food bin and more hammer OF - will check).
Cornish Cow
Since this is our most expensive city (I think) can you whip a Courthouse before a Settler? The city should be able to work two Cottages @ size 4, and thus whipping at size 5 is not an issue.
Food is decent in this city, I actually don't think this delays the CH by much (the Settler generates a bit of OF). The city has plenty of happiness to spare so the best use of its 2 good tiles is whipping a bit harder I think. I'll try to determine by how many turns this delays the CH.
If the Settler completes on T81, are two Workers close to Pigs/Wheat, and a road network in place?
Yep 
For a T83 settle. It's early compared to our recovering economy but it's a good city spot and the 2 Workers on site justifies the early settle IMO.
Sea Horse
How much

on the turn that the Granary completes?
Not sure either but the whip is pretty decent, that I know (the bin is definitely under half but it's not a perfect whip)
Dye/Stone
Obviously doesn't need to be settled on T79 if the site is not threatened by Tokugawa.
Sure but if we have 2 Workers there to improve the Rice why not?
(Farm will 4/5 at the end of T81)
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I won't harp on about our need for Missionaries in the north.

But I would add that Sea Horse needs a religion too, for the

. A border pop will let us work Clams and Horse. Either use a Missionary from Constantinople, or whip one in Sheepish.
I agree. I sent the first Missionary from Const to Dye/Stone but I think I'll send him to Sea Horse instead. Then again, as mentioned earlier, we might need an early border pop in Dye/Stone too (but I think it can be delayed).
After the Granary in Sea Horse is built, it can grow to size 3 by working the Corn and Rice. If Sea Horse is @ size 2/3, Constantinople can whip its citizens. When Constantinople has regrown, whip Sea Horse. Sea Horse can also 1-pop whip a Work Boat if absolutely necessary.
OK I'll look into those possibilities.
After the Grasslands have Cottages, Case Départ doesn't need more than one Worker, if that. I don't think the road 2W is needed (either move 1NE, Cottage/cancel; or 2SW, to move west; or 2S, to move onto the riverside Forest in Sheepish). We don't need a road on the Corn.
Some Workers can move onto Forests (= 1 turn), pre-chop (= 2 turns), and then pre-Cottage (= 3 turns) or pre-farm (= 4 turns). This will save Worker turns and preserve Forests until we need them, as long as you don't require the Workers elsewhere.
Yes I know, I built the roads because it didn't know what to do in transit I need to rethink this and take into account your suggestions.