Disclaimer upfront...islay fan here
interesting discussion, slightly sidetracked a few times by 1) esoteric arguments about whether Speyside warrants its own appellation (term slighty misused I know...), and 2) an adbot (johnniewalkerproject).
notwithstanding my observations at least partly afforded by the luxury of arriving the party late, here are my lists:
Ardbeg Supernova (but have to build into it with lesser Ardbegs)
Laphroaig 10 Cask Strength
If only one Scotch from here to infinity:
Anything other than Islay (Talisker excluded)