I would just expand on the previous comments. In this case having a buro, Maoi Capitol, working water tiles. migth be a really cool thing, both production and Commerce in one spot.
The advantages for this city as i see it is a ton of Food. You will have following food surplus, only conting tiles and improvments giving more than 2 food. Before sailing 3+2+2 =7, after sailing and a ligthhouse 3+3+3+1 = 10 after buro, 4+3+3+1 = 11.
I would had settled 1S. With FIN That gives 8, 3c water tiles(with moai thats basicly 2-3 "free" hills" that you can work while you grow). IMO getting the GLH is mandatory for this start, and with a IND leader. The colossos could also be a cool thing.
So you could easily grow into a bigger size when you get monarchy. while working "okay" tiles. Having a 20 pop GLH buro/moai/colossos capitol in the BCs?

I think it will give a higher Return from just overall tiles worked "more" water tiles than you probably would With a rivercottagecapitol With less food. It also gives the flexibility to be a GP farm, when you are in golden ages etc. You can also cottage/workshop some grassland tiles.
It's not the greatest start, but with the right strategy I think it could be really cool and different capitol.
OP: can you upload the starting save, from 4000 BC? I might make a emperor video about it

I just want to see how "ridicules" I can make this capitol with moai,colossos an that big of a food advantage