Painting on a toned ground may not be as disconcerting as painting on a white ground. As a matter of fact, the masters of old quite often used a colored ground of some sort. Painting on a white ground came into prominence some time in the mid 1800’s, mostly by the impressionists.
There is nothing wrong with painting on a white ground. Most artists today use the white ground as a starting basis for their painting. I paint on both the white ground and the colored ground as well. You would do well to try both.
A toned ground can and at least most often, affect the appearance of the finished painting, by imposing an overall undertone. Also, one might choose to leave some portions of the painting open, allowing the undertone to show through. If you were to do this with a white ground, you would end up with somewhat harsh white splotches in the painting. I believe this would be quite annoying unless it was done in a very diminished manner.
A colored ground can sometimes negate the total necessity of doing a complete under painting and/or the necessity of completely covering the canvas in the beginning stages, as it is already covered. The ground can be a neutral grayish color using umber possibly with some blue added, or it can be of any other color. Sometimes a warm ground will work well. It depends on the overall effect that you are striving for.
Most grounds are produced as a tint using one of the earth colors mixed with white. However, there is nothing to say that you can not experiment with any of the other colors. Also, an imprimatura glaze, which is a color diluted with a varnish of solvent and copal medium can be applied over the toned or white ground and allowed to dry before starting the painting. The varnish is generally made by mixing about five parts solvent with one part copal medium. If you use both a toned ground and an imprimatura, make sure that each dries well between layers and well before painting on.
You might even try experimenting with different colored glazes over different colored grounds.
In the painting below I applied an imprimatura glaze of yellow ochre and burnt senna over a white ground. This particular glaze seemed to impart an overall warmth to the painting, even though I covered the canvas with paint most completely.
You can view the videos of this painting on my you tube channel. https://www.youtube.com/channel/UCsvch2xXn9JeiAQv19t-bGQ