I need some help customizing Appointment+

I'm in need of something very close to Appointments+. Essentially I'd like to change it to where "Services" would be simply listed as classes and visitors could simply sign-up for those classes using Appointments+ plugin.

On the front end instead of a visitor selecting a service and service provider. They would simply select a class the pic from the available dates and times.

All other functions like response email, sign-up process, etc would stay the same.

Would this be a tough customization? I'm decent with php and mysql and have built plugins before for clients and for sale. I just wanted to ask to see if this had been done already.