daredevil123's advice is good.
TS, it's still not to late...
Make a decision on where to go for the outing. It's YOUR outing, so you decide. When there are a lot of confirmed details, people will put their names down... trust me. Just browse through the other outings threads to see for yourself.
It sounds like you don't drive, so I would suggest Esplanade waterfront. Yes... many people have photographed that place, but that doesn't make it any less captivating The plus point is that it's near to public transport. City Hall is also a central MRT stop, so that it doesn't discriminate against those staying east, west, or north.