Upgrade or alternative upgrade?

I disagree with the choice for level 7: Although Arcane Dragons have lost "Dragon's Breath" in the description, it is still present (+ you can apply the Dragon Form rune), and the small drawbacks compared to the Lava Dragon in the form of a fire shield, 5 armor, and 5 hit points are compensated by the rune, and as a result, it will gain much more.

Dragons cannot apply the Dragon Form rune.

Added 1 hour 51 minutes ago
1. For clearing neutral creatures, we take Alt. and fight defensively. In the final battle, we use Orig., as there is the possibility of protecting adjacent units.
2. For rushing and in the late game, only Orig. - crippling strike.
3. I never use it for clearing neutral creatures; I save it. In a battle against all races except Necropolis, I take Alt. It's clear why (Roar - Claw attack).
4. I never use it for clearing neutral creatures; I save it. Definitely Berserkers, I won't even explain why - it's funny, it's all obvious.
5. For clearing neutral creatures, we take Alt. - fireball. In the final battle, we use Orig. - cross attack, fire wall - we drive away archers.
6. We clear the initial neutral creatures with Trolls and regeneration. In the final battle, definitely Erls - if you can apply the right rune and position the dwarf, and if luck smiles upon you, the final battle will end ahead of schedule. The choice is clear.
7. We build dragons on Veteran level in the second week, and in the third week, we clear all neutral creatures without losses. In the final battle, of course, Lava Dragons. I won't explain, it's all logical - shield. If anyone has doubts, put Lava Dragons under the first attack of 100 or more Knights of Isabel or Paladins, and everything will become clear to you immediately.

Points 1, 3, 5 may be subject to discussion, but 2, 4, 6, 7 are not up for discussion.