But what icons to choose? There are a bunch of icons available in the Google Play but not all of them look as good as the stock do - that's why you should check it out: Best Icon Packs For Android!
All of these icons are chosen only by my taste - if you think I missed something: help me expand the list!
Nox, one of the most famous icon packs offers you over 1260 custom icons in FullHD resolution including 12 nicely-themed wallpapers. The icons are splendid and beautiful - they're very nicely themed in minimalistic style and one-sided shadow will surely make you to buy the pack.
Minimal UI offers you a little less value of icons but they're just awesome. Minimal UI icons are flatten, simple, pretty and not overdone. This pack also offers you 8 wallpapers themed for the icon pack. If you love simple and minimalistic icon style, you should definitely check this pack out.
If you combine Minimal UI and Nox icon packs toghether and add them a little dirty design, you will get this - Axis icons. These are my personal favourite - this pack has only about 775 icons but I personally think they are the best-looking. This pack also contains 6 HD Wallpapers suitable with icons.
Motif icons have a different style unlike others. These icons are bounded and have a slight shadow in left upper corner. These icons may not seem as the best for everybody but if you combine them with right widgets and wallpapers, it can look really beautiful.
Know better packs? Help me expand the list :)