Sometimes the lens is almost like a butterfly net which you only have to wave about and you find life sticking to it.. or that's how it seems on those days.
I do like using lenses in different ways: my Tamron 90mm macro was a soopa landscape lens, and I've always used a 21mm or its equivalent for both architectural and portrait.
The 21mm allows vertical-format landscapes to really develop an idea of movement and engagement, easing the viewer into walking around one's composition: an ultrawide lens provides a good strong foreground and "lays down the lines" in your shot whereby the viewer travels around.