Why?
If you havent noticed yet, every armor and helmet in the game has a color scheme, though some do have little twists or are applied awardly, or even combined. Those color schemes are the same as the accessory ones. The reason I believe we wont get new Roses is that we have almost all the color schemes.
Red- Weird Toasty
Black- ??? Weird heavy
White- Weird Divine
As you noticed, they all follow the base of their color schemes, but not exactly, which shows that they adapted this system slowly and progressively, or maybe wasnt even intended at all initially.
In second gen, you can notice this system getting more solid
Green- Military
Blue- Cool
Gold- Regal
And in third gen, they fill in the missing gaps
Coral- Fancy
Violet- Dusky
However, all rose sets have an added/grey or brown to make them ... well, be less like the scheme they are representing.
Only Volcanic and Prismatic are missing. God save us from the volc shap-vog coats if they ever realease those...
I also must say that I LOVE this concept, it supports pretty mix and matching... however it takes a while till people notice that in order to match their outfits. I sure hope they will keep following this concept and fix the equipment with heavily distorted or missing schemes (hinthint deadly and normal virulisk, chroma line, ancient, trojan masks, azure... etc.) so they will match even better.
Oh and if you are unsure about it, feel free to ask me about the coloe scheme of an item, I've become able to identify even the weirdest of twists.
I've kinda been wondering about the rose/personal color/other stuff matchups. I'm colorblind, so I really just have no good grasp of how the equipment visual scheme is supposed to work.
Which is why I basically just wear my white rose set.