When talking with Eric about the current drive system, he should concerns about having the front wheel the directly powered by the gearbox. Eric's mindset was that the power transferred from the impacts of the weapon would go directly into the small gearbox.
Some of the force would definitely be transferred directly into it just due to its proximity, but I still think the vast majority of it would go through. The frame stops located directly underneath the weapon. Most of the other force would be absorbed by the squishiness of the wheels.
Nevertheless, there is some validity to this. There's also a downside to having the weight gearboxes in the front as well as having them directly mounted to any wheel regardless of location.
What if instead of having the front wheel directly mounted to the gearbox, the gearbox was relocated to the center of the robot and the front shaft was replaced with a dead shaft.
This would assist in fixing the weight balance issue. Essentially right now the weight of the gearbox is which is roughly 23 g. Each is in front of the center of mass of the robot. This weight imbalance will cause the robot to want to front flip on spin-ups of the weapon. I believe it is more desirable to have weight further back in the robot at this point.
The gearbox should be harder to hit by not having a wheel directly mounted to it. The gearbox in pulley that it drives will be tucked away underneath the top and bottom panel and hidden behind the wedge. It'd be quite difficult to hit it without severely damaging any portion of the frame. When the gearbox is mounted directly to a wheel It can be bent far easier since the wheel has to be exposed and creates a leverage point.
By belting to both wheels the redundancy of the system is increased. Both wheels would have to effectively be destroyed in order to stop that drive side. In the previous version, the front wheel is the single point of failure.
The way the rear dead shaft mounts to the frame can be mimicked in the front. The front armor mount can be extended back slightly to create a tab that the dead shaft mounting bolts can pass through.
Placing the motors in the middle creates a bit more of a hassle with the outrunners, but the foam component insert should alleviate these concerns already.
The armor mount will have to be bumped out slightly to account for the increased pulley width. The drive motor is effectively directly behind this mount.
By adding a belt, the width of the front is increased. I'm worried about it getting too wide which would reduce tire surface area. It may be possible to swap to o-rings to drive the front and rear tires, or to split timing belts in half to reduce their width.
The front and rear wheel should be mirrored if possible. This is to reduce part count and complexity.
The front or rear wheel could have a spacer underneath it as well to offset for the pulleys if needed.
The pulley for this will most likely have to be custom. I see this option breaking down into two different methods, by gear stock and create a 3 mm bore and drop a set screw into it, or 3D print one and place it over a shaft collar.