We have this spot under our kitchen sink where there's a spot for the HVAC system to push air into the kitchen. The black item to the far left is our dishwasher. I believe these are IKEA kitchen cabinets and supports. You can see that whomever first did our kitchen cut the bottom panel to the right so that it would not restrict air flow.
I believe at one point I looked at the conventional air registers at Lowe's, but they didn't seem like they might fix this abnormal situation. Because we had a lot of kids' cars begin to drive down towards this air outlet, we eventually put up a wire mesh, but it's super rough and falls out frequently (in this picture it's not even centered).
What would be some things we could do here that would look better?

