I'm very partial to whisky and indeed whiskey too.
For Scotch, I like lowlands, speyside and lighter profile highlands, especially Auchentoshan, Glenkinchie, Balvenie double wood, Dalwhinnie, some of the Dalmore stuff, Glenfiddich, Aberfeldy and Glenmornagie. Islay and Islands I can take or leave, but on a cold winters day, returning home from a day of game shooting or stalking on the hinds, something peaty or iodine-y can really hit the spot. Talisker or Lagavulin especially.
The Japanese make some spectacular stuff in a vaguely 'Scotch' style and in some cases for surprisingly good prices. I was a bit snobby about their product for a while, but judged with an open mind and with as few preconceived biases as you can manage, it really can be excellent. Nikka in the barrel is a really good starting point here and I thoroughly recommend it.
Irish whiskey, I don't have the experience to comment with any authority, but some of the smaller pot still distilleries make some super smooth and thoroughly enjoyable stuff. The mass market, not so much and I agree (wonder of wonders) with Fair Hill that there's a bit of market saturation with the newer small batch folks relying on some random cask and some marketing to make otherwise perfectly fine whiskey into something 'special'. Either way, the Irish make world leading mixing whiskey for sure, and actually a genuinely good stand alone sipping product in many cases.
I'm now on my Bourbon adventure as I'm living stateside, and it's quite similar to Irish in profile in some ways, but with more of a breadth of tastes and styles. High corn, low rye, non sour mash is my preference right now, with a slight preference towards non-Tenesse style stuff without the Lincoln County filtration, but I'm a beginner in this space for sure.