TL:DR? In short, take 3 guild banner's planted, all group member's in same guild, all group member's same race. That's a massive investment to get those morale gain rates but your rewarded if you do. You have massive weaknesses also due to being racial and somewhat leashed to those guild banner's, so you double guess yourself on a full on pursuit situation.
Take 4 crossguarded IB's with 4 axe slams = 9,600 65ft AE frontal morale bomb conducted every 60 sec's due to morale per sec being 60. Take 2 Runepriests as your healer's for 100% upkeep on mountain spirit (pre-defensive morale cycle nerf). Looks like a super fun group right? That's literally a HAMMER UNIT from warhammer fantasy battles tabletop game which this game is based on... Group comp above is 100% not possible due to dirty slow morale gain rates. This game is just suppose to be faster then what player's think it should be.
Morale bombing is all about organization/coordination/positioning and survival. Single target deaths of a morale bomb component matter's quite a bit. Which mean's ST is actually kinda important in organized vs organized. But how often does that happen? So everyone purely focuses on ap AE damage. Not saying that ap AE damage doesn't matter but lacing in ST in your ap AE damage has importance also. Purely from the morale drain on death mechanic.
You can build a warband to have enough morale bomb that far exceeds the max health of the average player. Without breathing that hard I can make a warband with 28,800 instant damage 30ft morale bomb. All I need is the organization/coordination to pull it off. That's 4 shots of a gun I can bring to deal with the zerg. That's Theoretically 36 dead player's. I can build much larger instant damage morale bombs then 28,800 30 ft if I wanted too also. But it comes at a cost depending on class make-ups. AE instant morale damage is literally how organized play can counter number's larger then themselves. Raze bomb's is kitten's play compared to what this game was capable of doing.
The zerg will only shoot me once with their morale bomb because that's all they can do because they lack the organization/coordination/discipline to due anything else. Zerg play can't control say "only bomb with group 1, group 2,3,4 hold bomb for 2nd wave of their push." Zerg play doesn't have the organization/coordination and discipline to deliver several shots of morale bombs. If I lose say 6 player's to a morale bomb I still have 21,600 30ft morale bomb left. I still have 3 shots of a gun which can turn the tide. Which is still theoretically 27 dead player's. I personally don't even have the organization/coordination to pull off the above but I am actively working towards it.
Each death of a morale bomb component decreases the morale bomb coming at you and stagger's the overall strength. The morale level of everyone on your team is super important and ST death's stagger's that. Which is why ST has some importance in organized vs organized.