Unfortunately, I live in a veritable hot dog wasteland. About the only ones I can get are the national packaged brands, or maybe Boar's Head.
As for ketchup, I like almost anything on hot dogs. Jalapeno mustard, extra sharp cheddar cheese, onions (raw or grilled), sauerkraut, hot relishes, chili, pickles, ketchup, hot sauce, etc. What really got me was about 10 years ago I went to lunch with a friend of mine who's originally from northern Louisiana. I put ketchup on a cheeseburger and he almost flipped out. "Why would anyone put ketchup on a cheeseburger?", he asked. He acted like I was committing a mortal sin. I've never seen anyone react that way to ketchup on a cheeseburger. I can't imagine how he would have reacted if I had put ketchup on a hot dog. It's not like I was pouring it on a filet mignon steak. I don't eat at McDonald's anymore, but didn't they used to automatically put ketchup, mustard and pickles on most of their burgers, unless you told them not to?