I have two viewpoints on Heresy, based on experience being on either side of the skill/gear leap.
Early on, coming up through the ranks (and yes, I played Legend VT2 - didn’t buy the expansion), the jump from Malice to Heresy was huge.
I found several weapons I had been using just “didn’t work” at that level, for my skill. e.g. Trauma staff, catachan sword. Handling large hordes with a few elites thrown in is a huge leap from what you see at Malice T3. I’d just get swarmed.
I think it’s also the first time you really have to get in to the stride of melee first, gun second when things get tough, which is a fairly alien concept outside fatshark games.
As a T5/T5+ player now looking back; I hate playing Heresy … e.g. for Melk’s tasks. I hate it because there are players in there who are just a liability and not good enough yet to get through those levels, and so trigger a wipe. BUT - and I say this openly - that’s a ME problem. I’m in there for the WRONG reasons - e.g. to finish off Melk’s tasks, or try something out. I’ve a post here about that. But even so, me playing in there does lvl3-4 players no benefit - I’m carrying with damage.
Those are the issues (at least for me) I think with having a level that is not linearly between T3 and T5. And so, in a long winded way, I think the suggestion of keeping damage the same is a good one. But being hit like a truck from trash mobs vs. the scratch at T3 might be a step too far? I’m almost of a mind that T2 should be raised a bit, and T3 raised a bit too … rather than T4 changing. T4 is a good stepping stone to T5 imho… just right.