Someone prepared a very spicy meal for me that included an aji (i believe fruto) tasted amazing.
It's funny how a whole dish can be taken to a higher level with a great tasting pepper.
For sweet peppers I'd have to say Kapijas and Pimientos like the Hungarian "Tomato" pepper. For hot Annuums I keep coming back to Korean Gochus and Ancho Mulatos. The jury's still out on Frutascens and Baccatums, but so far my favorite Chinense is the Yellow 7-pot. It has a sweet, fruity flavor for about 20 seconds before the considerable heat hits...