Good info. I'm a newbie to Android and was wondering about launchers myself.
Here is some additional info on neat things launchers can do:
*worth it for this alone: can remove the search bar from the top of each screen and decide which format to use for the one you keep, if any - transparent ICS, shaded JB or now shaded KK with new mic icon*
1. Change the number of dock pages, usually up to 5 and add unlimited home pages.
2. Allow you to hide apps in the app drawer like wallpapers, bloatware you don't use but can't remove, or icon packs once you start using them. You can usually organize in other ways as well with pro versions.
3. Set transitions for your pages and scrolling type. For instance, have 5 home pages and at the last one? Next one is back to home page 1.
4. Can change the app drawer to scroll horizontally.
5. Can make your icons smaller.
6. Can add 1x1 widgets to the dock.
7. Can change the shape and layout of folders.
8. Can change the page notification bar and decide if you want a divider between your icons and dock.
9. Can rename apps or shortcuts so "Grandma Smith cooking apple pie", or rather "Grandma Smith coo...", can become "Pie Video".
The list goes on but these, along with the ones listed earlier, are my favs and the ones I miss right after installing a new ROM but before restoring my launcher. Will add to list if I think of more. Oh, some people like notification numbers (like on iOS). I didn't activate that feature. And this might be a rooted feature, not a launcher, but ability to turn off notification bar and dock areas. I get confused sometimes between what did what change.
Hope this helps anyone considering a launcher.
Sent from my "no longer 120? or battery guzzling" Sprint Galaxy Nexus, thanks to help from the AC forum