Questions:
1. What functionalities can I implement more?
ex: send sms to know what events are available for this weekend, then system response by a list of events.
You will need to contact a sms service provider, if you want to a hosted solution
Google : SMS Providers[
^]
admittedly this gives providers in the UK but you get the general idea
2. How can I implement a payment method for event ticket?
depends on how much work you want to do, there are many off the shelf ecommerce packages you can get
Ecommerce packages[
^]. You could also create your own.
But you will need to also get yourself a payment provider such as paypal etc.
online payment providers[
^]