Not a DRG, but I get where you come from...
Pretty much at 70, your combos will no longer be of 4, but 5 steps.
Wheeling Thrust and Fang & Claw now can proc 100% from Chaos Thrust and Full Thrust respectively.
They become a 5 steps combo because after a Wheeling Thrust you can now use Fang & Claw and also the other way around thanks to a trait past lvl 60. This will mean that DRG will become a bit more Positional dependent, since for example Chaos Thrust in the rear > Wheeling Thrust in the flank > Fang & Claw on the rear.

At least keeping BotD looks a lot simpler, and for rotation min-maxing I have little to none to offer, but it seems like the new red state, Life of the Dragon, is not something you can keep up 100% of the time, unless WT and F&C can extend the timer, which they don't specify.
Even on the description of LotD says that once it expires it will go back to BotD.