There is no hole for the LCA bumper as we are not running on that car, but it would not be a big deal to add the hole. I wish the companies making stiffening plates would run with the idea...........
Are those on the car and in use ? That tab looks like it will bend without the gussets tied back to the sides of the arms for strength.
The aftermarket stiffening plates are too simple to produce as thay are. No left hand or right hand, no various swaybar tab locations. They aren't even bent. To run with your idea would mean 4 more part types plus what they offer today for those who dont need or already have the factory sway bar tabs.
Anyway... I have 1/2 dozen arms here that dont have any tabs. If I decide to buy tubing to make my own frame ties I might make some of those tabs from the scraps.