Dear Madhu,
I fully agree with you. If it is only for two roles it is definitely not worth to develop such programs. Also I assume that the owner will not change daily, so probably you are doing that once in a long time.
Hence I really suggest to use the given processes from GRC. With role update you can easily update role owners and that takes you not even a minute.
Also be aware that a new development brings additional effort in the future while updating to a higher release. As you are also depending on the org chart you have one additional source where you can have errors.
Hence I do not see any benefit from that.
Regards,
Alessandro