You can do, as long as you delete, and NOT select "delete from iCloud".
You would also lose them all if you cancel your iTunes Match subscription, to they decide to drop it.
I do not think that the iTunes Match take up is huge, so I think it might go the way of Ping.
I would keep a local back up. I also don't think it will end up like Ping, because they just launched it in other countries just recently (March of 2014). Ping only lasted 2 years.
+1. ALWAYS keep local backups. Don't trust the cloud 100%, you'll be sorry at some point.