Try the official forums. There's more activity there. Also a user promoted weekly song challenge.
I switched from xbox to PC now.
You don't want to use the "rocksmith recommends" riff repeater. Because it's still using the old 5 lives system. If you go to the song from the song list and use riff repeater you get 30 lives.
Also when you finish a riff, before you click on continue journey (which takes you back to the first menu) look at the options, you can either go back to the song list or go to riff repeater or play the whole song.