Is there a way to hide application icons in Launchpad?
Unfortunately the only ways are to...
A) Put them all in a folder in LP out of the way or on another page you never go to like iOS
B) Move the applications out of the actual Applications folder into another folder (I do this for certain apps. I put them in a folder in my Home called Apps. Because if you name it Applications, it still puts it in LP.)
C) Be an Apple developer and have access to the blacklist LP uses to hide certain apps like how the new iLive and iWork suites will show up in LP but the old versions will be excluded. (Not sure how LP does this. It might be hard coded.)
Pick one. Remember, B only works with apps that aren't picky about their location. Like apps from the App Store or ones that need to be installed.
I agree though that Apple needs to provide real ways on iOS and OS X to let us hide apps from that list. Until then, these are our workarounds. I also wish they'd add pages to OS X LP folders like on iOS. But don't even dare make our folders on OS X only hold 9 items per page to compromise. Thanks, Apple. Get right on that for 10.10. (Or 10.9.1?)
Used the demo version of CleanMyMac 2 and noticed that the language adds on Dictionary takes a lot of space. How safe is it to remove those language packages?
This is only a guess but I'd say since they're self contained packages, you should be able to delete them individually with no problem. I can't guarantee OS X won't redownload them or have a fit. So do a test. Take them out and put them in a folder somewhere or in a ZIP and run the computer normally for a while. If you run into a problem, put them back. I can't see OS X being completely balanced on them existing since they're really optional. But don't fully delete them until you make sure nothing is wrong.