In praise of Art songs

A note to younger singers in praise of art songs: If you know you are going to be growing into a role but are not right for all of it yet, instead of focusing on just learning the arias look for comparable art songs either by the composer or a contemporary. If your teachers are assigning you art songs, shut up about how you want to sing arias and learn them first. Figure out what is useful for your development. Take them as studies for the larger things you'll encounter down the road. Seriously, it is in your best interest.
Example: I spent about 2 years working on, living with and trying out Wagner's Wesendonck Lieder. I worked through the technical aspects with my teacher, my trusted coaches and brought them to just about any/every master class teacher, conductor and coach I could get in front of to sing them. This year I was offered my first Brünnhilde in Die Walküre. Yes, the notes are different*, but the line and the approach to phrasing, the melodic motifs and harmonic progressions are so similar, that I have never doubted for a second that I could sing her and learn it all relatively quickly. The ease, technique, beauty and muscle memory learned in the easier-to-shop-around art songs have given me all the tools to make my first go at this auspicious role so much more enjoyable.
Finally, as my wonderful colleague Shawn Thuris pointed out, you are the vulnerable entity in an art song. There is no mask nor character to hide behind. This is huge in developing your approach to a character. What can you bring to her/him that no one has before? You won't know unless you find out what you personally have to say in that rep, and there is no better place to find that out than in an art song.

steps off soap box

*the most extensive Wagner quoting Wagner I've found thus far is "Weh mein Wälsung" in Act II Scene ii direct stealing of : "Wohl, ich weiß es" from Im Treibhaus (Wesendonck Lieder)