If I remember correctly the ez8 is only slightly cheaper than the Jackson so yeah its kinda redundant to get a ez8 when you can wait an extra minute for a better at option.
The Jackson kinda took the role of the ez8 and made the ez8 redundant. A strong at brawler but one has 60 range and better pen. Therefore I think they should take the ez8 in a different direction and/or a price reduction.
Rather frustrating that, innit?
With the Jackson being able to tank as a tank destroyer, there aren't a whole lot of roles left for USF tanks. Due to the Jackson there's really only anti-infantry duty (Scott, HE Sherman), an even higher degree of durability (Pershing), or being cheap/expendable in relation to axis units (M10). (And unfortunately the M10 is now 'too little, too late' to even fill that role well.) I find that for any USF commander you either want SP Artillery (Calliope or Priest) or a Pershing to support your roster lategame. Everything else in the doctrines are just for shits and giggles. Also, Jacksons and Scotts are still just as sick of a duo as they've ever been. Everyone talks Jacksons and Shermans but the Scott is a goddamned indirect fire sniper.
Ultimately I wish the EZ8 weren't a separate model from the stock sherman. It'd be great if the EZ8 were an upgrade rather than a unit. Either a global one like the CoH1 76mm upgrade, or as an individual 'upgun'. You know, trade in shell switching for a more accurate (model sniping) gun with better penetration, but little to no AoE.
It could even find a home in a variety of commanders or actually be a stock upgrade.