Auto-translated
As I see it, experience could be implemented here as: novice (0 experience), seasoned (1000+ experience), veteran (5000+ experience), elite (10000+ experience); just need to think it through properly.
We should discuss this (can you provide a link?):
1. I propose that they receive a defense bonus from experience (a shield in battle), and with experience, a serious bonus by the end of the experience growth will be +15 defense. As justification, there will be few low-level experienced units, and high-level ones get a similar bonus anyway in SoD, see below.
2. As experience grows overall, +2 speed would be added (SoD plays with Mullich somehow, right?).
3. Experience should be awarded to those who kill and be divided by their count (1 angel kills 60 Troglodytes and 20 Archers kill them, the angel should get more experience) and (1 angel kills 60 Troglodytes, his experience is multiplied by 1/7, level 2 creatures by 2/7, and so on; while Archers killing Troglodytes have a coefficient of 1/2, killing angels a coefficient of 7/2, and similarly for all, though ideally the coefficient should be 14 (upgraded and non-upgraded version, something like that)), is this feasible?
4. As experience grows overall, attack and defense will increase by 6 by the end (analogous to the hero skills Offense and Defense).
5. Health will be 20% higher by the end of experience growth.
6. By the end of experience growth, +2 is added to both maximum and minimum damage.
7. When upgrading creatures, the experience amount should be preserved (if an angel is a veteran, the archangel should also be a veteran).
8. If you add a novice angel to a veteran angel, the difference in experience is divided by 2 (veteran experience - novice experience / 2). Then you'll start thinking about whether to take that growth from novices into your army.
9. Pandora's Boxes and other things do not give experience to the army.
I want to hear if I've missed anything, write about it. And your opinion, how do you like this?
Regarding morale for neutrals, I completely disagree (it should exist, or an analog like in HotA). In HotA, they did it well by adding artifacts for morale and luck