If there is one thing I've learned its that this game doesn't do "jack of all trades" units very well at all. The best "jack of all trades" unit is probably the regular Sherman. So, two Easy 8s cost 760 MP and 280 fuel, that's a lot, that's a friggen King Tiger. This is not really a spamable /blobbable vehicle, it's expensive. So needing more than one to be effective points to it's poor design. The Panzer IV is a better example of a good all around unit. It's deadly against infantry and pretty good against most vehiclea (also seems to come out REALLY fast).
This is a clear case of the "grass is greener".
Easy8 is superior to Panzer J and come at the same cost and is hardly "useless"
In addition Panzer IV is not "pretty good" against vehicles it can fight and win vs meduims (although slower than most of it) but it will probably lose to Sherman 76mm and will be almost useless against anything above it.
This so much. Having 3 versions of shermans that are very similar is bad game design.
The bad design does not come from the version of Sherman that are not very similar (accept for dozer Sherman and 105mm which is bad design) but the ability of M36 to completely shut down PzIV from range 60. There little reason to built Shermans because there are better investments like double bar riflemen, Scott, M36.