Oil change intervals shouldn't go by color anymore because engines are burning cleaner, and can go 10k miles and still look pretty good.

I'd suggest going 3-4k (max 5k) miles on conventional. If you do a lot of city, go closer to 3k. If you do a lot of highway driving, lean closer to 4k.
With synthetic oil, I'd suggest 5-7k (max 10k) miles with the same rules as above(5-7k).