Bolty,
When you take all the allowances into account and the reduced cost of living in Singapore I think that the offering is reasonable. However when you look at the !!!! they dump on you, the offer is insufficent. I don't know what coverage or licence type you have but there is a few Brit's (8 that I have been told of with more compatable licences to the CAAS licence starting at SQ either recently or in the near future. (The CAAS licence is now a B1 and B2 type of licence.) So I really do not think that the wages are going to increase significantly in the near future especially for CASA licenced individuals.
The new roster that you mentioned has not yet been implemented it is going through now and should be sorted in the next week or so. It is a 4 on 3 off format with changes to 2 off after a few weeks to make sure that you do your monthly hours. This should reduce the cost to the company of wasted O/T hours.