Since you have indicated your choice of high perks and would like to have respect of your staffs apart from having adequate time for your family and considering these angles I would recommend you to go in for the CAT preparation so that you join one of premier institutions such IIM Bengaluru , IIM Ahmedabad, IIM Kolkata etc. Even selection of the stream should be such that it should be just like a hot cake in the market. Better option in this respect giving you tremendous opportunity is the Finance Stream followed by IT.
To sum up, if your giving your best shot in the CAT test proving your caliber of high order, you would get your preferred choice both in terms of streams and locations.
Salary would not be a constraint factor and with the progression of time you will feel elated with your prudent choice.
Now considering that you have taken up GATE for making up career in the Public Sector, it would not be a bad idea since in the event of your final selection, you would be fitted in their existing basic scale with the two additional increments as a mark of your achievement of GATE qualification.
Here salary is not the problem since they would pay you hefty perks because of upward revision of the scales but the only drawback at present is that you have work for an extended hours. There is the possibility of your over exertion in such an assignment. Sometimes, you have to manage the work of the next shift, if the officer of the next shift has not turned up.
Now talking the prospects of IES, you would be satisfied with the pay scale and your future prospects, but here also you will have to work hard even with the extended hours making you dull and exhausted due to their working environment.
You may decide your career considering the pros and cons of such engagements.