I like my tea unsweetened and strong. This is due mostly to my upbringing. I like the second steep almost as much as the first.
Sweetener: Almost never. Prefer honey or even maple syrup if I must.
Milk: Chai definitely, orange pekoe, some other blends, but in general, I skimp on the milk too.
In the summer, I brew ice tea cold in the fridge, no sweetner of course.
Favourites: Not a definitive list. I grew up on Chinese teas so I tend to favour them.
Blacks: Oolong, Assam, Ti Kuan Yin, Yunnan
Greens: Lung Ching, Sencha
Blends: Earl Grey, Chai, Lady Grey, Prince of Wales
Tisanes: Mint, Licorice, Honeybush