Hello.

• People in GSEB generally never communicate in English language. This makes them feel outcasted when they are taking to their counterparts from other CBSE or ICSE board. But, eventually when the need comes you shall develop the required skill. Its not a big deal.
• The syllabus earlier was quite outdated. But now it has equally matched the other boards. Yes, the teaching pattern hasn't changed much, which needs to change.
• Exposure in terms of extra subjects is the major drawback of GSEB. I would give 100 points to CBSE/ICSE in this case.

 in a longer run, nothing makes any difference. It is all on you, how you adapt to the society where you are living in.
 

As of now it is better to be in CBSE as people around in CBSE schools are little competitive .

Hope this is helpful.