hi Anyann,
I heard of 9frames but haven't seen their works yet.
I am not sure about william Chua or Lyrical moments.
For me criterias of choosing a photographer is quite simple, and we did not look much because it will confused out.
1) The comfortable level with the photographer (1st in priority)
2) The feel of the pictures
3) The price (what I did was I went to search for photographers, I saw kwang, fieldberyl, tinydots, and hurricada) but found it was somehow similar, so which is more affortable I took)
4) Where will the photos be after wedding? No doubt photos will be there for memories, I don't agree that a more affordable photographer work is not good for keeping sake or. just think thru, when we were young, our parents took photos of us, they are still valuable today, while looking back at it, so whats important is the feel of the photography
These are just my own personal opinons
Cheers!