I'm doing a "Catch em all" crystal run where I catch and train every single pokemon as I progress throughout the game (some obviously require trading), with the ultimate goal of completing the pokedex. Just finished catching all the route 29 and 46 encounters (including phanpy) and am now gonna move onto route 30. I must say, I'm really enjoying myself so far, but I wanted to ask anyone who's done this sort of thing so far for advice, anything you learned that you wish you had known before hand or whatever, that sorta thing.