There is one real benefit to putting your Mac to sleep vs. power on / power off. You have probably noticed that after you have loaded an app for the first time after a power on, all subsequent reloads of that app are MUCH faster, since part or all of it is still cached in RAM.
If you put your Mac to sleep each night and awaken it again each morning, you preserve this behavior and all your most used apps just "snap" into being when you start them anew. I love this incredibly fast response, and so I use the sleep/wake cycle on my Mac. About once a week I reboot just as a form of clean up.
That would be my recommendation - saves power AND delivers blazing fast start up times.