Think it's going to be harder?
Nah, it never got that hard. It would've been even easier if I wasn't trying to train up some of my lower-levelled pokemon.
The best ball is the dusk ball because it works at night and in caves.... That means anywhere.... It's 4x more effective than a Pokeball.... Only better thing is a master ball.... And the best thing is they're not rare at all....
I'm trying to be more diverse in my Poke Ball choices. For example, I'm catching all pokemon I fish for with Lure Balls. I'll definately be using Dusk Balls at some point, though. Especially when I start hunting for Legendaries, since a lot of them are in caves.