You do not say if you are applying for the mortgage because your developer has a mortgage with them? If this is the case than you dont have much of a choice as any changeover will incur additional cost of say around Euro 35550 -5000.
In respect of current account they are all the same, Go through with a very fine comb inrespect of charges. specailly cheques/non cash transfer into the accout as a % is applied this could become a sizable amount.
With some banks you if you get their credit card and other services you could shave of 0.25% of the intrest rate on your mortgage.
There is a lot of competation and lets face it you will be borrowing 60 to 70% where is the Banks risk.
Negotiate hard.