am not convinced by the concept of '浮动配套的相对风险大些银行随时可以宰你的'. Based on my understanding, the rates go according to SIBID but not anyhow defined by the bank. Local bank is always a better choice compared to foreign bank for variable package.
still believe as a consumer the bargaining power is very limited. Not sure how it works for hdb loan but as a corporate banker, only those customers that can bring us million dollars would be considered for preferential pricing.
whether you would be able to get an ideal package is not depending on your barganing skills but controlled by the market situation. should not compare the package you signed up earlier on to the package bankers offering now as the market temperature has changed.