Personally, I never had any issues with the feather proc chance. I always have enough (3 or 4) stocked up for burst phases, and have never found myself lacking save for synced content where it doesn't matter too much anyways. I don't really think much of the Fourfold Feather needs to be changed. The RNG doesn't bother me, but I mained BRD all through SB, which was nothing but proc-based Crit RNG, so I guess that's why I don't have issues. Nor do I have issues with the Esprit gain - my static is very good about giving me my Esprit for my burst windows. :3
I feel like me having no complaints about the RNG is an unpopular viewpoint.
The suggestion a few posts above me of the Flourished procs from Flourish granting 100% feather RNG isn't a terrible one. I just wonder by how much that would boost our damage, and if they would have to take potencies off elsewhere to compensate. Or if we would end up more balanced with BRD/MCH. I think it's a fairly reasonable suggestion.
Tl;dr - Overall, the RNG isn't an issue for me. But I also mained a heavily RNG job last expansion so maybe that's why, and I'm simply just used to it.
The only change I would want to see is Saber Dance as an oGCD. I get so sad to see good Esprit RNG overcap my gauge while I'm just trying to fit everything else in my Technical Finish windows. Even if I spend Esprit before my Standard Finish during it, I'll watch it jump from 30~40 to 90~100 during the 5 seconds I'm dancing, and it just feelsbad. This doesn't happen every time, but when it does I'm staring at my Esprit gauge making a face.
The change to oGCD would probably mean a slight potency hit (though I think DNC could stand to not have the potency of Saber Dance hit too harshly given how it is the lowest physical ranged right now in terms of rDPS by anywhere from 100 to 300 rDPS last I looked at rankings), but I think it would make Technical windows feel a bit more smoother. I like the busy feel of DNC burst, but it sucks to not be able to fit it all in because of good Saber Dance RNG. A short CD of 3s to 5s Maximum would suffice, I think; even 1s would be fine. I just think it being an oGCD would be much smoother.
I don't think Improvisation is an adequate enough reason to not make Saber Dance oGCD, simply because the skill itself is used only during fight down time unless you weave it for a healing buff (I've spoken with my static healers for this and they've yet to tell me of any spot in Eden Savage where they would want it, so it's mostly unused for me currently unless I pop it to build up Esprit during E1S or E4S transition phases). It's not a skill you use on CD - it's very niche just like SAM's Meditate. The only change I'd want to see is to allow it to give 10 Esprit flat per tick for if you attempt to weave it in for the healing buff. It annoys my OCD to see it tick and give me a Esprit amount of, for example, 8. Then I have X8 Esprit all the time, and that just bothers me lol.
I think DNC dmaage could come up just a tiny bit - maybe by 100~200 rDPS. But I don't think we're in dire need of pDPS buffs. It's not as it we're massively behind the other physical ranged like RDM and SMN are to BLM, or NIN and SAM are compared to MNK and DRG. Our job is a support job that can easily bring 1,500+ rDPS to a group with just our Dance Partner and Technical Finish, so we should have lower pDPS by default.