So, now prestigers are pretty much useless? Did you transfer your Pokemons? Who did you leave in your box? How many Pokemons do you have?
I don't like having many of them so I always transfered a lot of them, same as now. Left ones with 100% IV. 98% IV if it's somewhat usefull Pokemon with somewhat high CP. And 89% plus IV Pokemons if they are high CP and usefull in current meta.
I'm left with:
145 Pokemons at level 35