There is no magic powder that I couldnt live with as when I run out of a powder I usually can use another powder until I can get some more. What I use is as follows.
Pistol
Bullseye covers most of my plinking needs using cast bullets in 380, 9mm, 40s&w, 38special, and 45 acp.
Accurate #2 for 9mm with berrys 115gn plated
Accurate #5 for 40s&w with berrys 180gn plated
titgroup for 38 special SWCs (2.8gn Bullseye for wadcutters)
Unique for light 44 mag/ upper end 9mm and 40s&w
Hp38 for cast 45acp round nose
lilgun for upper end 44 mag
and a couple other powders that I try from time to time
Rifle
WC844/WC846 for plinking 223 rem
Xterminator, for hunting 223 rem
blc-2 223 rem and 30-30
H4895 30-30
IMR 4759 for cast rifle loads
H4831sc .270 win, light 7mm rem mag bullets
R22 7mm rem mag, 270 win
And a few others that I use for special projects.