Alright, after a bit of extensive play, some thoughts:

1) We are gated behind 2 layers of RNG to obtain our feathers. 1st layer being the combo proc, and the 2nd layer being actually obtaining a feather from those procs - this feels a bit too much. My suggestion is either a) Always generate feathers from the procs or b) Have a , but smaller, chance to generate feathers on non proc abilities. Flourish is good to generate feathers, but there's that awful chance of not getting a feather - at all - from the procs generated there and feels terrible, so suggestion c) is to have flourish always generate feathers from proc'd abilities

2) Saber Dance being on GCD feels slow for a resource spender type of ability. If nothing is done regarding the above item, then I'd suggest it being turned into a oGCD, even if it was necessary to slighty nerf the dmg or add a small recast timer to compensate.

These problem with these 2 items above is because DNC can either have a really smooth and dynamic gameplay, or a really slow and clunky gameplay, because our weaving-in oGCDs abilities are gated behind the mercy of RNG luck. So, in my opinion, would either making feather generation a bit more reliable, or making Saber Dance an oGCD.

3) Curing Waltz needs the range doubled, because the utilitiy of the spell is almost negated if you really can't catch a lot of people (sometimes including yourself) in the double heal. In my experience, the only moments you'll find the party intentionally REALLY stacked in that range, is to make sure everyone is receiving Cure 3 from WHMs... but then, in such occasion, Curing Waltz wouldn't be that useful, since Cure 3 is already very strong.

4) En avant range also feels way too tiny. I'm the only here that thinks like this?

5) It would be lovely if the developers could find a way for us to keep Closed Position with the chocobo partner. Also... No idea how to solve this, but the dps dummy trial, for dps check is useless for DNCs because we can't account for step damages.