" Yabapmatt had stated Delwyn Dragonscale would be the only summoner outside the water splinter that would get a buff to magic attacks. That was the official answer to why he had a mana cost as expensive as 5. Archmage happened soon after.
As a really big card in the SEED/Germinator-campaign, this was a huge blow on some of the investors' trust. Even a single occurence can serve as proof we should fear it happening in the future. "

I am completely agree with this point. You are right that Archmage was announcent later than Delwyn, but he was playable before Delwyn, as the Orbs started before you could redeem the TRON-token.

Instead of thinking about their investors of the SEED/Germinator-Campaign the done it later even worth by reducing costs from Archmage from 6 to 5 Mana.
So they sold cards, spoilt their worth worse before you could reedem them and a little bit afterwards make 75,2% (common drop-rate) of this cards nearly worthless and I cannot see any movements in this point. I wrote this also here:

https://steemit.com/splinterlands/@schachoberhessen/q1hcxf

two month ago but nothing happens till today.

I cannot understand why - If the investors from SEED/Germinator-Campaign would be worthful I think the mana-costs of Delwyn would be already reduced.