Curious, does the launcher allow other changes, like the clock on home page. Just one example but imho Samsung the up[date is truly a step BACKWARDS.......
The home screens and app drawer aren't actually part of the operating system but are provided by an app called a launcher. Each manufacturer includes their own launcher, but Android allows you to install and use a different one instead. So if you install a third party launcher you will have to set up your desktops again on that one (some do have options to import setups from other launchers, but you'll find some work is needed anyway). That said, different launchers give you different capabilities, e.g. Nova allows you to change the size of the "grid" (numbers of icons you can place on the screen), position things more flexibly, put folders in the dock, have multiple docks, etc.
So a third party launcher will allow you to have a different clock on the home page, or no clock at all if you prefer. It may not actually allow you to put the Samsung clock there, since many manufacturers produce widgets that only work on their own launcher. Some of these, such as the HTC sense clock
@ocnbrze mentions above, have been copied by third parties so that you can have the same look on a different phone or launcher. Personally I prefer to use third party launchers, widgets and apps, because that way when I change phones or update the OS I don't have to change my setup.