Dear Sir!
It's really great to write my proposal here for your website page needed to be improved with Customer Booking Plugin/ShortCode.
Having read all that you posted(customer subscription, rewards program, offers, coupons, vouchers, and game booking options), I am sure I can deliver the perfect results, as I have already developed many Booking plugin for same service , although it's phone communication time and food delivery and so on.
With the exact understanding of payment depending on your website , I would like to suggest you Firebase Cloud Notification service and Cloud function/Localstorage as a additional part, to implement SMS system functionality for successful or failed Booking process and reduce your Site server usage.
If you have any questions about pricing or need to increase or decrease the scope of work, kindly just let me know.
I appreciate the opportunity to send you this proposal and I look forward to working with you!
Sincerely,