Which is preferred? Block houses or loading zone houses?

Hey guys, I am relatively new to Pokopia and while I'm progressing through the zones, I can't seem to figure out which is better: The "block houses" with no loading zones or the "Prebuilt houses" WITH the loading zones?

I know the game has a limit on how many pokemon can be "outside" and sometimes this means I can't find who I'm looking for. It's convenient to run by a house and see who's inside for the loading zone houses.

However, I do love seeing the pokemon all walking about.

What are your preferences and why? Thank you!