Darjeeling is very nice black or lightly sweetened. It's not an overly strong tea. In fact, it's rather delicate. But the taste is really complex and it is my favourite tea of all time.
For herbal, I've stumbled upon a Twining tea that's called "Spicy Apple Chamomile". Back home, I used to drink Traditional Medicinals ginger tea. It was very strong ginger (meant to help upset stomachs), but I love ginger. It's right up there with avocados and olives for me.
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I haven't been able to find anything quite a strong here (or any Traditional Medicinals for that matter), but I do drink Twining "Ginger Lemon" which is good but overly strong. In fact, I am drinking a cup now.
Green and white teas were a big thing for me last year, but I hated them before I learned to make them properly. You can't boil the water and you have to steep it really quickly. A lot of people get turned off by stewed green tea.