Updating AC supply/return registers throughout our house with Pacific Registers, exactly like these examples.

For our ceiling diffusers, can I replace with single or double-directional louvers to achieve the same functionality as the current diffusers? Do you recommend single or double-directional for those? We have a few variations -- see photos below. Are there pros/cons from a functionality and air flow perspective?

Of course this is an aesthetic decision that not everyone agrees with, but for our specific space and budget, we prefer the look of the custom registers. Hoping I can get info around functionality specifically. Thank you in advance to this wise group who can provide so many helpful insights.