This thread over at ANN has some good suggestions for shows on Crunchyroll. I'd add
Chihayafuru to those lists, but less because of the quality of animation than the quality of the story.
As for
Dennou Coil, there are a few people still seeding the Ureshii fansub
here. The links on the
AS page for
Coil died when the Scarywater tracker site was discontinued a couple years back. GHDpro hosted a back up of Scarywater here for a while, but the
Dennou Coil entries all point to the dead tracker. There is also a Coalgirls fansub based on the Japanese BD releases and the Ureshii scripts, but I can't point you to that site since the tracker hosts licensed content.
One other show I'll recommend for its production quality is
Ghost Hound. It combines both beautiful graphics and a remarkable soundtrack.
Ghost Hound is by Shirow Masamune of
Ghost in the Shell fame. He also directed another show for Production I.G called
Real Drive that has excellent animation quality.
In general I'd suggest looking into shows from
Production I.G and
Madhouse if you're looking for high-quality animation.
Brains-Base and
Satelight are two other excellent studios.
If you're looking for stunning artwork, there's no better choice than "
Bakeneko," the third installment of
Ayakashi Samurai Horror Tales, and its unlicensed sequel
Mononoke.