What are the benefits of running a bitcoin daemon?
You will not get anything money wise from running bitcoind, however the Bitcoin network depends on people running it for verifications.  Its providing a service to the rest of the bitcoin community.  I run it because I participate in the bitcoin community and want to give something back.  

This is how the "decentralized" part of the bitcoin protocol works.  People like you and I run the daemon and it verifies everyone elses transactions, the more people who run bitcoind the more secure the network becomes.

As for your other questions, I can't speak to speculation and this website will suspend your posts if you ask opinion or theoritical questions.