I think your idea has a potential. You are asking if it is...
Business is a risky thing just bear in mind that you have already target client who are willing to try your ideas. Seek a businessman friend and market yourself and your ideas to him/her. When he agrees with the deal, do your best so that if your target client likes it, you can attract many other clients.
If there is a demand for this?
Yes. As you said, it can help companies to advertise their product. They may not need HR in the future and other benefits that you mentioned. So, that's it. The finer the benefits, the greater the demand. Business nowadays needs advancement in technology in order to develop. You have the capability so use your talent.
How can I go about marketing this?
My answer here is the same with my first answer. Build your confidence to a friend and prove to him you're worthy.
Good luck! I know you can do it. You have the talent. All you need now is self-confidence