My favorite is still the one that introduced me to hot peppers - the Scotch Bonnet. I was introduced to them eating for a week in Jamaica, then via various bottles of hot sauce I brought home from that trip in 1991 - Scotch Bonnet based brands have been my hot sauce staple ever since. In 1996 I got some smokey powder from a friend that made it himself from large dark red peppers he got from Belize - he showed me boxes of these peppers, and they were beautiful. He said they were Scotch Bonnets, but my understanding is that they would actually be habaneros; however, the flavor was much nicer than the tiny habaneros I get here. This same person owned a barbecue restaurant in Atlanta and had a 'hotter than hell' night each month where the entire menu was based on pepper-enhanced dishes of a particular culture. I was there once for Native American night and it was one of the most memorable (and hottest) meals I've ever eaten - everything was enhanced with his Belize habaneros.
More recently I picked up a 10g bag of dried Scotch Bonnet pods and ground them up with a mortar and pestle, hoping to get a similar powder. After everyone in the house started coughing and sneezing, we put on masks and I finished grinding them outside. I wet my pinky and touched it to the end of the pestle - couldn't see anything on my finger, but it was still incredibly hot. Now I'm looking forward to the peppers on my plant ripening so that I can begin preparing them for sauce and powder. Hoping to find some good advice here for those two processes.
I cannot describe the flavors as well as any of you, but I really love the dark red Serranos (in very small doses) and the spicy dark red anaheims (both in my garden this season). Also, I had some cajun belles last year that were incredible, but my own plant is not creating peppers with the same spiciness. And finally, my newest pepper introduction - roasted shishitos with sea salt (Sunday morning).
I haven't yet met a pepper that doesn't have a place in my diet.