Remember, this is a novel written by a woman who broke tradition with the writing of Jane Eyre, a highly feminist work for the era. On the literal level, Jane as an artist illustrates her eye for beauty and being able to translate that beauty into art. On a deeper level, Jane as an artist accomplishes a few of Bronte's objectives. First of all, it raises Jane's social status, for even though she is a poor governess, as an artist, she is talented. Secondly, as an artist, she can see the world in a unique, observant way which sets her aside from the other women in the novel. Lastly, it serves to make Jane a very well-rounded woman who finds self-realization at the end of the novel and is more than worthy of her own independent life and marriage to Rochester
At first I think her art was a way for her to escape reality, but as the novel progressed it seemed like her art was how she stood out. She was always referred to as being plain, but her art was anything but plain. Besides her smarts, the art was the only thing that could give her some status as a poor woman in a wealthy environment.