This is simply a filter to me, and this cannot possibly "improve" airflow but more likely reduce it a little. The only way to actually improve airflow it to clean cable clutter inside the case and change/add higher cfm fans. The push/pull config inside the case is also very important because you don't want a fan blowing hot air back into the case when another fan worked hard to get it out
The Honeycomb design in a filter is to help air flow, as some filters block or hold back some of the air flow from the design of the filter. larger spaces= better airflow.
The honeycomb design on a grill is to to help airflow , because, as you pointed out, it is less restrictive, the filter media itself negates much of what the honeycomb does.
The fact that the Silverstone filter is nothing but sheet metal means that it cannot "direct" airflow the way the thicker honeycomb in the link I provided does.