most of the homeschooled kids I know are weird and clueless when it comes to social interaction.
I don't think I'd say most, but some certainly are incapable. And how are you sure being in school provides a better social expreience? I get most of my learning from classes with a lot of kids. I'm in a shakespeare class the I'm performing in, and there are 20something kids in the class. I take a lot of intellectual classes as well, which make the best IMHO out of a class experience.
Like I said, if parents choose to homeschool they ought to make sure their kids are getting a good amount of social interaction, and it sounds like your and many other's parents do. I said most homeschooled people I know, I don't claim that was an accurate representation but just something parents ought to look out for (I would also say you should be concerned about your kids social interaction at a public school). I said I would send my kids to public school because for me it is important to be exposed to many people of different backgrounds, not just religious but social classes as well--though of course that also depends greatly on the school.
As for the school for arts question, I am getting a degree in Creative Writing and I'm not fully content with my decision. It has certainly helped me in several ways, and has perhaps exposed me to certain things I wouldn't have found on my own, but ultimately it's not very necessary. One thing going to school for the arts does do, though, is give you an excuse to do nothing but work on your art for four or so years. Once you get a full time job, etc, then it's really a test whether you will have the energy to stick with it--after fours years it of focusing on it it seems like it will be easier than if I jumped into right after high school.