CA with b com

a very wrong question and a very wrong comparison.

CA is well recognized only in India (and in some parts of the world). But the catch is if you do not have any Bachelor degree, you would be considered, in academics, as only a "plus 2" person. It might be a dis-qualification for you to travel to some countries and get the processing done in faster pace for any perm. residency. Example for what I am saying is USA. Indian CAs need to apply in EB3 only as they do not have bachelors.

I would say, plan to do some Master degree as well (like MBA). It is very essential these days to get recognition esp. in foreign countries.

As to scoring, you want to be reasonably good. So, try fro 80% you might get 70% which is okay. But if you get 55% or 50% it might be okay but you can't give your marks sheet to anyone or say you are in second class with a high level degree like CA. So, do get a good score in bachelors or masters that you do.