Put the light where the plants want to have it, dont think about the diatoms.
Dont crank it to 100% if your tank and plants arent ready for that.
Focus on growing your plants well, your diatoms will disappear in due course. They always do.
Put the light spectrum to where you think it looks nice. The plants will grow either way, this is the simple and liberating truth. 1% growth increases from a super specific spectrum matters only to those who are producing massive amounts of crops on an industrial scale.
I really empathise with your struggle because there are so many conflicting views out there.
K.I.S.S. principle is a good rule of thumb when you find yourself lost in the jungle of advice, at least I find it useful personally 😊