Still a lot of great whiskey's out there but I'll try to stick to my tops for each category. Obviously not the absolute best as you asked to keep it in budget and just as Johnnie Blue isn't worth what it costs, we can also find great spirits at a budget.
Bourbon
Bulleit 10 YO - 45.6% Cost: ~$50 Dry, bitter, best to add water (experiment with the amount) and let sit for 10-15 minutes to really open up and balance. Warm vanilla and dried fruits/spices really come through.
Four Roses Single Barrel - 50% Cost: ~$40 Rich, sweet. Definitely add water to this to cut the spirits. This develops very well in the glass, it starts fairly citrusy but as it develops with water the more mellow honey, vanilla and rose notes come through.
Scotch
North Highland:
Glenmorangie Original - 40% Cost ~$40 Warm, sweet, great finish. Preferred neat, if you add water just a drop or two as it's only bottled at 40%. As the name implies it has strong orange and citrus notes. If you want to spend more money the 18 year old is my favorite Glenmorangie bottling. It's summer in a glass with an amazing silky mouthfeel.
Islay:
Caol Ila - 43% Cost: ~$50 Peaty, briny, warm, like being at a bonfire at the beach ;-) As with the Glenmorangie, just a drop or two of water as it's bottled at 43%. Great if you're looking for something that isn't Lagavulin, Ardbeg or Laphroaig.
Lagavulin - 43% Cost: ~$50 (Costco) Peaty, phenolic, pungent, warm. Again, not too much water, experiment with different amounts. Allow it time to breath and open up with the water, it will lose some of its bitterness and the slight sweetness will come through. Overall a very full and intense whiskey, not for the light hearted.
I rarely drink Irish but the ones that Tom_G mentioned are the ones I prefer.