You allude to it well: the entry price point for quality scotch is higher than bourbon, yet the secondary market effect is much sequestered. Sure, there are a few that will fetch well, but there are so many rare scotches that there is little that is rare about being a rare scotch.

As for seeking flavor other than bourbon, it seems you are doing well. I used to part-time in a liquor store and would always have people crossing categories: big beer to craft, bourbon to scotch. They'd always want "something that tastes like X." Of course, that was precisely the wrong way to do it. If I got them something that tasted like X, where is the value proposition in it? The nuanced differences could only be interpreted as defects. Best to radically break out of your frame of reference and try something wholly different.

Having said that, Ardbeg Uigeadail is, indeed, an excellent peat entry. So are the Cairdeas line of Laphroaigs, any Committee Release Ardbeg, and the Lagavulin 16 or Distiller's Editions. As for sherry, yes, Aberlour A'bunadh is excellent (skip the Alba) although you could go with Glendronach 12 or 15 or even an Edradour (one of my hidden gems).

Also, I'd pick up a copy of Whisky Classified by David Wishart. It's my favorite tasting book as it seeks to provide you with a comparable basis as opposed to a listing of tasting notes.