When you installed Nova, there should have been an option to import your existing desktop pages. Then everything would have looked almost identical to what you had before.
What is SO ugly? Nova (like Touchwiz) looks like how you want it to look. You can put all your app icons on the homescreen(s) and arrange them any way you want (with a lot more options in Nova). Ditto for widgets. You can apply any wallpaper you want. It's only as ugly as you make it.
What's the best launcher? No such thing. There are a number of popular ones, and some lesser known ones. Each offers certain features and options. What I think is best might not be best for you. You can look at these threads for some opinions and ideas:
http://forums.androidcentral.com/member-favorites/30411-vote-your-favorite-launcher-here.html
http://forums.androidcentral.com/me...what-your-favorite-launcher-2012-edition.html
A simple search will bring up many more:
http://forums.androidcentral.com/search.php?searchid=3170566
To change it back to the default: from any home page, tap the menu button, then Nova settings, then scroll down and tap "Select Default Home" and choose TouchWiz. My suggestion would then be to uninstall Nova, and re-install it, and this time pay attention to what it's doing, and tell it to import your existing home screens.