If we talk about opportunities then ECE has more scope than ME. According, to the trend in the market you should go for ECE branch. Mechanical engineering is an evergreen engineering field. This field has very good prospectus in the Govt and as well as in the private giant construction sector.

As an electronics engineer you can indulge into both your core field and as well as in the software field if you want.

Major software MNCs have requirements of engineers of ECE background also.

So, both the fields are good you should choose the branch according to your interest.

Good Luck!!