Feels like it's going to be forever before I get Tyranitar, Dragonite or Ampharos- so many candies to get!
I have three Tyrannitars but I got them all from raids; any candy I get goes to powering up my best one. As a consequence, I don't have a Pupitar yet 
Dragonite took me ages to get but he was well worth the wait. Ampharos, second best electric in the game after Zapdos, I managed to hatch two Mareeps during the double event to get him.
I have all of Gen I bar Dodrio, which I'm walking. (Though I don't have Tauros or Farfetch'd as they're regionals, nor Mew or Mewtwo as they've not yet been released.)
I've only got 7 regular Pokemon out of Gen II to get as well, so I'm not doing too badly 
That's why I'm hoping it'll be Spring before Gen III hits, because for those who haven't finished Gen I and II by then, the release of Gen III will make it so much harder to complete previous pokedex's.