Here were my thoughts.
Get 8 bottles, 2 from each of the major reasons, with generally one a little more modest and one more expensive.
Speyside -- Aberlour 16 (a personal fav) and Macallan 12 (your classic scotch)
Islay -- Laphroaig (a classic unique scotch) and Lavaculin 16 (agree with the recommendations here)
Highland - Oban 14 (I think this one is pretty friendly for non-scotch drinkers) and Aberfeldy 12 (never had but seems like it has good reviews for the price point)
Islands -- Isle of Jura (Brooklyn) (I think all the Jura stuff is good) and Highland Park Dark Origins (love HP, never had this one, figured this is as good a time as any).
Thoughts? Anyone ever hosted a large scotch tasting like this -- if so, any tips?
Thanks guys!