Online Activity Reservation System

I am looking for a simple to use but powerful system to handle booking reservations for our Activities (Guided Horseback Trail Rides, Carriage Rides, Llama Treks etc.) and Events (Pumpkin Festival, Halloween Hayrides, Outdoor Movie Night etc.). Once a guest has selected an activity or event we would like to be able to offer add-ons that relate. Some of booking are by the person or by the unit. For example Halloween Hayrides we are selling tickets to the event for a particular time and date. For a carriage Ride we are selling the carriage itself and it will carry up to four passengers. When the zoo is open for the season we want to sell tickets at various price levels depending on the day of the week or number in the party. Would like to be able to make up packages to sell for example... a romantic sleigh ride for two with roses and hot cocoa. We do need the ability to create a custom event on the fly for a client like a company outing. Calender must display in an easy to read format for the staff. Must be easy for the user and our staff to use. Very clean screens and booking procedure. We currently use [login to view URL] to collect payments. We would want the system to send confirmation at time of booking, a remind prior to reservation date, and a follow up email regarding our services. We do current use "Promotional Codes" as discounts. We work with daily deal sites like Groupon , Living Social and would like to be able to import voucher codes so guests make book directly online. I am really hoping someone out here has already developed a great Activity based reservation system that could be slightly modified to meet our needs. I am hoping this person after viewing our current website will have the perfect match. Our current website is www.VisitTheFarm.com. We are in the process of developing a new website and looking for a more modern, simple, clean reservation system.