Some suggestions based on the last trip which I went with Leinaj:
5) There is mini van or small lorry selling drinks outside the entrance so you may not want to carry too much water.
6) Travel by the van will be easier especially the walk may tired you out. Moreover, you may need to rush back to jetty if you stay a bit longer while waiting for others. Also it getting back to the jetty fast you can have your drinks at the coffee shop at the jetty area.
Actually the amount of water u carry really depends on what mode of transport u choose. If u walk, u'll definitely need to bring the most amount as those who went thru NS before will know. If take bike, it's in the middle and of course van is the most relaxed and won't need that much water.
If we choose travelling by van, it's fast and relaxing but u can't stop too often along the way.. it's like a taxi like that, brings u to your destination and that's it. Unless we wana book the van the whole day.. then it's a different story. But I don't know how much it costs though.. can go there n ask n see how. So far I've never seen vans parked at the side of the road waiting for PGs to shoot in my trips there..
For people who like to shoot macro insects, there are alot of big spiders and webs along the roads which I only saw because I was walking all the way. Even if u're on a bike, u might miss them, so if sit van, confirm will miss them one. But walking is really shaq..and u won't be able to cover the whole island in 1 day, because chek jawa also need to walk.
So I feel the best compromise is to ride, then u'll have the flexibility of stopping where ever u want and can still cover the ground in a relatively quick time.
I've thought of a couple of extra stuff :
Things to consider in the details:
1) Meeting point - I think we can meet at Changi Village itself at one of the stalls in the market, then at least can have breakfast while waiting.
2) What happen if there are latecomers - As from the last meetup, I find east shooters quite punctual, which is good. Maybe wait for half hr?
3) Equipment (cam, lenses, bags etc) - Insect repellent (I think it's a must to bring, but can share), sunblock, hat, comfy walking shoes, sunglasses if u wana look cool while shooting. I'll also bring a small bike lock,because chek jawa inside cannot ride bike, so gota leave it outside. It's not really a case of the bike getting stolen as opposed to someone accidentally ride off with yr bike,which I heard has happened b4..so jus a precaution.
Then the rest of the cam stuff are standard I guess depending on whatever u wana shoot. If u have CPL or ND filter, can consider to bring because chek jawa got a boardwalk out to sea, so if the day is sunny, u'll get reflections on the water.But don't bring so many things till u can't ride properly.
4) Attire - Up to u I guess, I'm wearing tee n berms and sandals.
5) Food/drinks - Bring enough water.. i think 1L is minimum if not more.. there are some drink stalls scattered along the island though..
6) Transport on Ubin - Basically 3 ways. Walk, ride or van. Van is $2 per trip, walking is free, bike I think $2 also have but lousier type of bike.