It's a solid unit in both doctrines it appears in.
And its just coincidence that Lend Lease is garbage doctrine nobody uses? Imagine t34/85 in a doctrine with fuel drop, that would be instant meta commander, and 76mm costs almost the same with much worse performance.
Only way to make 76mm viable is increasing its HP and AI slightly (like 75mm AP round AI) and removing HVAP shells (just because ISU152 has ammo switching doesnt mean that IS2 has to have it too, same for shermans).