I think variations are key for the deadlift, seems to be what people are doing with this type of training (Tom Martin, Siders etc). I think at least some if them need to be rotated off the floor though.
In regards to stuff feeling lighter, I'm the same way. It wasn't long ago that 400 felt rough on my back, yesterday's 600 though didn't feel too bad at all.
On another note; i feel like after the meet, some more balanced training will be useful long term, leading into next year.