Heroes 5.5 WarGame Edition - Tactical Edition.

So, why do we need this formalism? Wouldn't it be better to move them to level 5 since they already meet the requirements?

Based on the fact that 6R = 1D and 3R = 1A, we get: 6R = 2A, and from this, 1D = 2A, meaning angels are twice as weak as dragons, but their growth rate is also twice as high?

Well, yes, but then the quantitative and qualitative contrast with Tier 7 will increase, which, in my opinion, is good - in my understanding, 1-2 epic units like dragons should be against a couple of hundred ordinary soldiers, not against 40.