Pre-turn: Spend some time reviewing our advisor screens. These can be very useful since they tell us a lot.
We are running 20% science and 20% lux. Invention is due in 8 turns.
We are paying 90gpt unit support.
As well, we are building Sun Tzu in the capital which will need to change. Since most of the main island already has barracks and Sun Tzu would only count for that island (similar to the English island with the pyramids) it's unnecessary. We can either dump the build and lose 40 shields or see if there's something else to do. Well with invention Leo's can be built. We'll need to get invention finished faster...more on that in a minute.
If we are going for a space victory we are going to want to run a much leaner economy and not build things that cost money without benefit. For instance, a library in a city that can't support the costor produce beakers is not necessary same goes for barracks if we can't make units in a reasonable amount of time. These corrupt cities can be beneficial. They can focus on settlers, workers, galleys, buchets(don't need a barracks) and occassionally a harbor for food. When these cities grow they may be capped at 6 pop and that's when you maximize food beyond 12 fpt and start using either tax or science specialists. The specialists will accelerate the pace towards shooting a space shot.
A few things will help us towards our cause.
Start by disbanding, as Chukchi suggested, a number of regular warriors, archers and spears and upgrade a few vets. MP's are not necessary in republic unlike monarchy. In fact, I plan to disband or use in war all of our regular swords in the Viking war. If they can't promote to veteran status we don't want them in our army.
Next, I notice we have 2 luxuries on the Viking continent that are not available to our Spanish continent or English continent.
Rush a harbor in Alesund for 112g. This will bring those luxs to all our cities, give us 4 native luxs and allow us to lower our luxury slider to 10% (~17gpt) and allow more citizens to work the fields. Not a bad investment.
Science...ok well we can either turn science up to 80% to get invention in 2 turns however we'd lose ~143gpt. Instead we convert some of the corrupt Viking citizens into scientists. This allows us to get invention in 2 turns but science at a 50% rate losing ~43gpt. We will lose even less once the luxuries come online next turn.
The Japanese warrior standing two tiles away from Blue Eyes which holds a pile of artillery. This makes me nervous. As well, there's a galley outside of our English holdings where we have no units garrisoned. Rush a archer in Blue Eyes for 24g and I'll send back a galley with swords to England.
Last, I wake a bunch of workers on the Spanish continent and send them to a mountain. Mountains can be powerful shield producers for cities that have the food to support the lack of food.
OK here we go...
560 Japanese warrior walks into our borders. A Viking galley drops off a reg. MI at Trondheim. Alesund finishes its harbor, Blue Eyes get its archer and Canterbury trains a worker.
In the battle for Copenhagen we lose a couple reg. swords but they've done enough damage that our elites finish the job. Get some slaves.
The reg. MI that is dropped off near Trondheim needs some attention. We only have one unit in the area but he's elite.
We attack and...
I think about rushing the FP but decide to make an army of MI instead. This may come in handy with the Japanese closing in on samurais. We may need it.
Like Copenhagen, we start with reg. units and finish off Odense with vets and elites. Cash rush a court in York. This town has some good potential on the english continent. Rush a settler in Hastings. Move all but one artillery unit out of Puppyville in case the Japanese warrior does something funny. Land the swords back in England. More units on their way back to England.
570 Japanese warrior continues past Puppy. Phew.... Invention finishes and start research on theo. We want to get education (for universities in our core cities) and towards astronomy for our UU and our eventual GA. York finishes its court and starts a rax. Nice improvement for the city. Puerto de Lobos trains a MI and starts another, Seville the same, Hastings trains a settler and starts a harbor, Toledo pike to MI, Punkbass MI to a lib, Tereul galley to temple for food. Nice add ons to the palace with some spires, landscaping and a 2nd floor. Iroquois finish Sun Tzu!

Well we really lucked out there since we finished invention we can move it to Leo's Workshop. Let's give hard thought to building wonders. If they can help us in a space shot, fine. The best one to consider IMO is ToE and Hoovers. We have a fair amount of time before we'll need that.
580Mongols ask us to join their Egyptian war. Nah but thanks. Birdjag MI to a market. Frozen Tundra galley to settler. Egypt starts SoZ and finishes it. Well that should make that war a little more interesting. Move on the final city.
590Whack a Viking spear/settler and get some free workers. Move units along mountains towards Stockholm.
Puppyville finishes a harbor.
600 Lose some regular units again but...
610Cleo asks us to join her cause versus Genghis. Nope. Would be prudent. Puerto MI to FP
this should be changed to something else. Knight?. Turn science to 0% with 1 scientist to get theo next.
620 Toledo MI to MI. Dang! Both the Japanese and Ottomans get theo this turn. Japanese start Sistines.
Notice the Iroquois have chivalry. Dial him up and structure this deal...
The cool thing about this deal is since the Iroquois and that continent don't know the Ottomans or Japanese they are willing to pay monopoly prices for theology. A very good thing we know everyone because we can get monopoly prices on a lot of techs. Same goes for chivalry now with the Japanese and Ottomans.
Knights are a strange build at 70s. 14s gets them in 5 turns and 10s in 7 turns. Kind of weird numbers. Anything more or less is not enough or too many shields. Still we need some speed. Start one in Seville. Since Knights of Templar doesn't cost unit support I switch from Leo's in 22 to KT in 4. Should help us to have a 5/3 unit against sams and possibly sipaphis later.
After that trade we get this one from Japan. I don't want to give him chivalry since he can build samurais with them. The extra lux helps a few cities.
630[b/] York rax to knight (10 turns
weird number I tell you. ) Conventry trains a worker and starts a settler.
Iroquois begin Sistines.
640 Trondheim worker to settler, Aarhus same, Logrono duct to rax, Mircy Waters settler to harbor. Iroquois move KT and Japan starts Leo's.
650 Reykjavik worker to worker, Blue Eyes from temple to worker, Dog Town from 'duct to MI.
Summary
Things are looking really good. Our unit support is still high at 60 gpt but we only have vets and elites. There are few swords that we could disband or upgrade since they are becoming inferior units. We should send our free units to the Viking continent to be prepared for a war with Japan. Japan with samurais are dangerous but I think we can avoid them but using the army against them. We will get education and should start on astronomy for our conquistadors and GA. We still have 17 turns left on our deals with the Japanese and Iroquois so don't start a fight with them.
Here's the impact of those luxuries...
Before
and after...Chukchi has been mm'd for commerce since it will finish KT next turn. You can put it back on shield tiles next turn. Many times I'll move off shield tiles to commerce tiles when it doesn't impact the finish time. Puerto can be switched to another wonder if you want. It's probably not best suited for the FP.