Thank you All, I really appreciate your feedback.
It has helped me a lot to understand the MBP performance related stuff.
I have made up my mind to go for following:
Only thing i need to check is if possible i could get 16GB ram, which i think in India its not possible.
13-inch with Retina display [I already have 22" monitor which i will use for big display output]
2.7GHz dual-core Intel Core i5 processor (Turbo Boost up to 3.1GHz) with 3MB shared L3 cache
128GB PCIe-based flash storage [I already have external 1TB Storage device ]8GB of 1866MHz LPDDR3 onboard memory
Intel Iris Graphics 6100
Let see i going to visit one of the store.
Yes one problem here is India doesn't have Proper Apple Store, where i could get the some more option.
But yeah i am going with it.