Somehow I missed when RawTherapee added the feature for bulk editing. Thanks for pointing that out in your article. Maybe I should give RawTherapee a new try :)
I'm glad you found something useful from the article. I have discovered ART [0] from the comments here, it looks like a better RawTherapee and I want to try it out soon.
[0] https://bitbucket.org/agriggio/art