I had an idea for the M10 in another thread, but I never did post it here in the feedback one.
Maybe they could take away the HVAP shells, but give it the same penetration values as the Easy Eight, move 'Flanking Speed' to Vet 1, and add a penetration bonus of 30% at Vet 3.
Current M10 weapon pen (140/160/180)
Current EZ8 weapon pen (155/165/200)
Then it could more consistently engage mediums from the get go without needing to spend muni, but without the HVAP would require greater numbers to take on heavies (which is/should be the Jackson's role), though if you've got one to vet 3 it'll be worth keeping alive as well with the increased penetration (202/215/260)
That cloak ability from CoH mentioned above would also be very useful in helping the M10 stay relevant for ambushes too.
The unit is a Flanker and should be used similarly to Puma to engage enemy vehicles from the side or the rear. I has enough penetration to do that.
Actually the unit was very cost efficient until 2 changes too place:
1) it required tech
2) M-36 was buffed and now it has to compete with the M-36.
So my suggestions would be to simply make it a call-in and build-able from major for a discount.
Since the unit is specialized it should not create many issues as a call-in as long as it in an commander that does not have AI call-in vehicles available to him so that he can completely skip major with not drawbacks.
In other word simply mode the unit to mechanized, it suit the commander thematically and enhance the commanders specialization of using lighter vehicles for a strong early mid game.