For techs, I traded Aesthetics for Alphabet with Sury and Alpha for IW with Joao. Joao/Sury have Maths, and Wang Kon has MC. I am considering:
1.Poly > Lit > Music
2.Currency > CoL > Philosophy or CS (maybe gets us a religion)
3.Engineering perhaps, but hope we can trade for Maths/MC rather than self tech
Well, worker management...

. The road being done... shared riverside between southern cities being ignored.. sigh.
I would also prioritize finding remaining AI(or multiple), the one(s) Wangs espionage goes to.
Very unfortunate that you could not trade for Hannibal's fur, Khmers seem to have share amount of tundra so you should check if gets some happy resources for trade.
1. Music is worth only if you can obtain Philosophy in timely manner. IIIRC, GArtist Philo bulb is not available with masonry.
Great Library is cute, but if it is target you need workers starting quarry+road, maybe a mine too. Novgorod could build but it has no real surplus, so best option is the capitol...
2. I would not be sure you get Maths in trade so fast unless someone builds HG. Not sure getting religion is worth anything at this point (free missionary to make Jao heathen maybe). Instead you should open borders with Budhism founder and hope for missionairies.
3. In some games it can be really long time before someone trades MC. At first no AI techs it, then overvalue due to Collosus...
I would probably go Currency, cause it gives immediate bonuses - trade routes, build wealth, smooth tech trades with gold, sell minor techs... Revalue after Currency, but likely Poly>Literature because I would want GScientist points going forward (and I'd hire two dorks in Library next turn).
Alternatively you can try teching MC and trading it for Maths/Currency/CoL whatever else becomes available. With Math/Alpha as prereq I would guess Currency might be the first tech obtainable via trade.
I think choice is about future plans, Currency>LIterature is more play for further stuff (post Lib). MC with stashed GE is more about moving towards trebs/maces/elephants.
While Curency>Lit into Liberalism is a lot of value in theory... Jao has a really nice chunk of land.