I've been kinda lucky myself when it comes to deficiencies. I use GH 3 part flora, and just assume they have the balance correct in their recipe. Normally I do 2 feedings and 1 plain water. If I see any deficiency at all, I skip the plain water and feed full again. Everything just seems to work out

. I duno if I could handle dosing 1 specific nute for 1 deficiency, hope I was right and having to wait a week to see if I made the correct choice.
Also cal/mg is my favorite since I switched to RO water. It Phs my water perfect every time. I rarely even test my water anymore. I do seem to see a decent amount of apparent mg deficiency so I'll ip the dose on the cal/mg a bit, but that's e only nute I really adjust for specific probs. I really dint k ow what's in the 3 different colors exactly to be honest, so I just feed everything based on the instructions and growth phase every time regardless of deficiency, unless I see possible signs of burn. Even is cases where I may have over nutes, I feel like I get good warning in advance where maybe I get slight yellow tips and I can skip a feeding and avoid Amy real problems.
I also wouldn't worry about a leaf or 2, even my lushest healthiest looking girls seems to always have at least a couple fucked up looking leaves.