Seems like more obvious solution would just be to make the detpacks less ubiquitous. Limit them to bombers and engineers, for example. Would give tanks more of a fighting chance against infantry and would require infantry to actually work together to take out tanks, instead of 15 people all lobbing detpacks at once. Also could be countered by slightly upping the power of those AT rifles. It should be harder to destroy tanks but easier to disable them.