+1 on the other recommendations for Lagavulin 16 and Talisker 10.
If you want something less peaty, give Oban 14 a go.
A great non-Islay, non-Island, peaty dram is the Longrow CV. I love this bottle, and it is very reasonably priced.
At (or near) the price point of the HP 18, though, I'd look at Talisker 18, Ardbeg Corryvreckan, and Springbank 18.
Great recommendations...if you like smoke and peat give Laphroaig 18yr a try. Reasonably priced and it's a great dram. 15yr is even better but you can't find it many places anymore. Right now I have Talisker 10yr, 18yr; Laphroaig Quarter Cask; and Oban 14yr. Just tried Ardbeg 10yr for the first time and it was fantastic - also worth a look. However, Lagavulin 16yr has to be my #1...MMMMmmmmm. ;o)
I love scotch and am always looking forward to trying something new. Good luck!
...oh and always neat, never OTR. ;o)