In fact, we will pay you to reap the benefits of being a Timber Affiliate. I envision agaves and yuccas alongside palms and cacti. They associate extremely well with those plants. They're very easy to mix. I like them mixed with colorful perennials or colorful wildflower beds because I think they offer a lot of contrast.
Agaves fit very comfortably with a lot of different planting styles.
They work well with Mediterranean plants - they look great. I've seen them used in ways that are very formal and in fact very stylized, and they look fabulous. If you buy a tiny agave plant and you don't realize that it's going to turn out 6 feet tall and that far around, you might have a problem. Knowing the ultimate size of the plant is the best defense against having one that takes over and becomes an unexpected monster. You can grow a very wide range of agaves in containers.