My first exposure to extreme metal was Dimmu Borgir during the Puritanical Euphoric Misanthropia phase. I had friends that were into the older BM a few years later, but I could never get into the "true" BM. I also cannot ideologically support the National Socialist bands.
I prefer Swedish metal bands as it is...so I have a few albums from Naglfar and Watain. I like 1349 'cause they're focused on the music itself and have decent production. I also enjoy some of the dark ambient bands that seem to be popular in the BM circles. I think Agalloch is brilliant as well as Wolves in the Throne Room, both bands being from the PacNW of the US.
IMO the Norwegians have taken it all too seriously, given the events surrounding Mayhem and the Second Wave bands. I respect Gaahl for his art and his integrity toward his Norse background, but the man is absolutely insane.
As a solo musician, I really look up to Quorthon for being so innovative with Bathory.
As for the question "Do Aspies love BM?" I think there may be a higher incidence than among the general population for a number of reasons. I think the attitude of DIYness, of finding your voice, and of rejection or questioning of social norms is attractive to Aspies. Historically, BMers are pretty introverted and may have developed a resentment for the way the world works. Also, I think we may have a higher capability for tuning out the harshness that is often present, as well as being able to understand what is going on in the music.
As for the difference between Black and Death metal, I see one factor standing out the most: guitar tuning. "True" BM will never leave standard tuning. Cradle of Filth has used various tunings, including the most un-black metal Dropped-D and its variants. Dimmu Borgir has been using 7-strings predominantly for quite some time. Hence neither band being considered part of the sub-genre. Lower tunings lead to more defined riffs due to the loss of clarity when playing so low at such tempos...why do you think Nile plays at half-time so often? They're tuned to dropped-d down a fourth(AEADF#B)- incorrectly known as "dropped-A", which really implies AaDGBE. Anyway, more defined riffs detract from the "atmosphere" of BM, leading to bands being separated from BM.