If items #2 or #3 are of interest, please contact support and we'll get it set up for you since these features are not yet configurable through the admin dashboard.
With any/all of these options, you'd need to use an external tool for the survey itself, since we do not currently have this built in. So your survey invitation will send guests off to whatever tool you use (Google Form survey; Qualtrics; Survey Monkey; etc...)
One final note... Exit surveys can be problematic because chats don't always have a cleanly-defined end (or beginning). Students who have grown up with instant messaging tend to see online interactions as an extended, asynchronous interaction, as opposed to us oldsters who grew up with the telephone model. In practice this means they tend to not pay attention to "End Chat" buttons and just wander away instead. Or leave the chat open for hours and then try to resume later. All of this makes the "end of chat" a moving target.