Maybe a little too cost efficient but I think Americans need something like it since their AT with doctrinal tanks is very iffy. I would be fine with slightly increased cost and cp but not a lot. However, the overall American AT picture should be considered.
Jacksons don't listen to commands half the time and if you tell them to hit a panther in the distance they will blatantly ignore you and shoot at pioneers instead. This unit is supposed to be mobile but due to bad pathing or commands being lost in lag it is a coin flip as to whether they function as you intended or not. They also start turning 90 degrees at inappropriate times. I think an SU 85 is more mobile since it has no choice but to shoot what you point it at and doesn't start spinning circles like a bored child when ordered to just sit there.
I want E8s to stay as AT effective as they are since I feel Americans can't do solid consistent anti tank play with what they get in their ties now. Also considering the crap AT gun that freezes solid for no reason frequently. Increased cost or cp, sure.
l2p i have been using the jackson a lot lately and its the best tank destroyer in the game. but why use a combined arms when you can spam a generalist tank like a nab and throw every lesson you learned about combined arms out of the window. if it would be up to me i would not only increase the fuel cost of all medium tanks but decrease their AT as well.
Soviets and am have excellent TD's. but why use it when you can go the nab route.