> You can only catch one pokemon from each catch area (route, town, cave ect) and it has to be the first encounter. Any further encounters in that area must be fought to death or fled.
> You must nickname your pokemon (allowing a stronger bond to be created)
I can imagine it makes you much more wary about the state of your pokemon and how you treat them, making the game much more realistic. And awesome.
*updated with my version of the previous bulbasaur sketch :D