Put everyone in same cabin. With sufficient planning, it's doable.
i don't think it's possible to get 4 suite saver seats on a flight or 4 cx f seats on a flight. I was lucky to get 2. I could have done 4 business on both flights but I wanted 2 f seats.
Honestly I don't know why everyone is going crazy about the split cabins. It was never an issue for us. We were together for 12 days we didn't have to be next to each other the whole time.
The only thing I regret was booking 1 economy seat on jfk to sin. If I could do it again I just would have booked 2 j and the 2 suites. But it ended up working out either way.