your questions regarding the game rules (improving the interpretation).

Regarding the upgrade of butterflies, I would allow it, because often the 2nd level is not built, and upgrading butterflies on 111 means losing phoenixes on the first. This would add variability to development. Previously, butterflies were banned partly due to long battles on the SOD timer, but now we have a chess timer. So I suggest discussing unbanning them as well.

I have also been thinking about butterflies for a long time. After all, without some spirit of despair, a single morale will wipe out your entire "imba stack." Besides, yes — the birds won't be built. However, if the second level is available from the start, then Conflux gets fairies from the start and birds on the first, which would be quite tasty. But not significantly more imbalanced than, say, Shakti with three stacks and Griffin Conservatory doubles, etc. But butterflies are still a more or less debatable unit, though they shouldn't be overestimated — the bot shreds them with ranged units, and neutrals kill everything on morale rolls. And in Dragon Fly Hives and Griffin Conservatories, they will also be useless, because they will be devoured immediately.