I did a quick study of a house plant today with a new palette set up. This new palette is very similar to my usual palette, except with a few additions. I've added cadmium yellow light, cadmium red light, rose madder, alizarin crimson and prussian blue. I've also switched out venetian red for a brown red, which I like more.
I didn't have any cadmiums on my palette for a while because I felt like they were too powerful (same thing with titanium white). I added them back on my palette to add another level of intensity for my yellows and reds, which I really enjoyed. I still prefer silver white (zinc + flake white) instead of titanium, which I find to be too cold and chalky. Prussian blue is a color that I used to use years ago and I like having it back on my palette. It's basically a very deep greenish blue, that comes in handy for darker greens. I switched out Venetian red for a different earth red called Brun Rouge because Venetian is kind of a weird earth red that I didn't find useful.
I always want to stress that the colors you use should be colors that you find useful. For a beginner, it's good to try out a basic palette, but remember to keep testing out new colors and find colors that work for you.