Not really, no.
There's no pressing need to remove one of the fundemental defining features of the USF around which the entire rest of the army is balanced because you don't like it.
Read the thread, most people say Jackson is kind of OP. I can't see your point.
So, you can nerf the performance of the Jackson or fix a bad fraction mechanism, which has more potential.
-> US has too quick repair options in combi with a 60 range high pen outrange vehicle. e.g. an Elefant has bad time to get repaird, because of bad repair of Ostheer's pios. That is kind of the balancing of Ostheer. And the balancing of Jackson? You build 1 or 2 Jackson, a M8A1 to one- or two-shot PaKs and HMGs and hunt down tanks without any real counter, instead of commander enities.
Please, don't say the M8A1 Howitzer is balanced. It has way more potential as a StuG E, or even a Brummbär because of its range and turret.
All over all, change the repair mechanism of US crews to bring them to a normal level. Then nerf the M8A1, let it perform like a StuG E's shell. That would balance the fraction without adding new vehicles to US meter.
Edit:
- give US vehicles a critical repair ability.
- lower the repair speed of crews to Ostheer's Pio level or even lower.
That would be my opinion.