I think a /pay [USERNAME] [TC] would be helpful, while also adding a confirmation command (for safety). This could be as:

Originally Posted by Confirmation Notice

Are you sure that you would like to send [USERNAME] [AMOUNT OF TC] TC? Please enter /payyes or /payno to input your confirmation. The payment timeout notification will override this payment within 30 seconds.

This way newer players will be able to take a look at what they are doing, before they complete the transaction.

Originally Posted by Payment Timeout Notification

Your last attempted payment to [USERNAME] of [AMOUNT OF TC] has been canceled. In order to retry this payment, please enter the command accordingly. /pay [USERNAME] [AMOUNT OF TC] after typing this command, enter /payyes or /payno to finish the transaction.

It just cancels your payment. It's just for precautions on multiple accounts.

Originally Posted by Payment Success

Your transaction has been completed! You have successfully sent [AMOUNT OF TC] to [USERNAME]!

A confirmation notice so that you know you have successfully sent the player the according amount of TC.

Originally Posted by Payment Canceled

You have canceled your transaction to [USERNAME] for [AMOUNT OF TC].

A notice so that you know you have successfully canceled your payment.

I think this would make paying players TC a breeze.
Please, feel welcome to post your responses below.