That's really funny. You want to start a DDL site and you're asking some absurd questions, on which only you can answer.

If you think time is passing by, and you haven't achieved anything. Don't be obsessed with that, you're still learning and there is a lot of time for you. So better go and practice, learn some basic stuff. And ideas will come eventually, reason why I'm telling you this is that you're still not able to think of a domain name yourself.

Good luck.