Ideas and suggestions.

What you described in the first paragraph is exactly what solves the problem that people mentioned above))) You can get a lot of things in the Abyss, so go ahead and take that Abyss creature. But a Shrine level 4 and a Guardian level 4 are very, very easy to obtain, and it's not comparable to the impact of an early Arcomage on the game.

So far, out of all the Arcomages I've seen in streams, 100% of them were used in the final stages of the game, after the Abyss. I haven't seen anyone "build an early Arcomage and immediately crush the opponent" even once. Perhaps it happened to someone, but given the rarity of this event, changing the Canon specifically for it seems like a dubious idea. IMHO, you need to look for a different idea.

When you suggest an idea, think about whether it will actually help? And what to do if it doesn't help? The approach of "added -> turned out to be bad -> rolled back" is not a kosher way to balance the game.