I draw a lot with mechanical pencils in .5, .3, and .2 sizes. Discovering extremely fine mechanical leads in a range of values was an absolute game-changer for me! My mechanical pencil collection consists of:
.5 in 6H-4B
.3 in 4H-2B
.2 in HB-2B
I use my .2’s and most of my .3’s in every drawing. Because the lead is always so sharp, the 2B in these sizes lay down wonderfully dark.

In terms of regular pencils, I love Mitsubishi Hi Uni’s 10H-10B. They’re sooo smooth and buttery, and the 10B is the darkest graphite pencil that I’ve found.
I also couldn’t do without my 10H-7H Koh-I-Noor Toison D’Or’s. On drafting film, this brand of 10H is noticeably lighter than Mitsubishi’s 10H. I often have people comment on my heavy use of the hardest H’s (many people just ignore 10H pencils!), but I find that they’re the best finishing tools for smoothing out subtle transitions between light and dark.