Well. Actually they both have their own specific quality but if you are in interested at working on pc, laptop ,and you are interesting in coding then no doubt you should go for CSE. And In CSE there is only private sector job with decent package.
And yes ,first of all, mechanical is tough than other branch But if you want kick then surely join(jokes apart) obviously mechanical is core branch and of course you can get govt job as well as placement from college. But Its mechanical so understood is that there is shortage of girls . But i think its better .
Now see..every branch is best . Ofcourse if any branch is exists ,then no doubt it will be best future safety surely. If you are passionate for your branch then everything is perfect. But its engineering so just one thing keep in your mind that ..dont take stress just fun and more fun…
Best of luck..