is it also by design to make three domain (like, three different domains) decks nearly unplayable? or to be a disadvantage to players expecting a certain draw (e.g., I want my great oak when playing my 3S deck ... not my diplomat). these are the reasons I find the card OP.

I never had problems with Trade Routes when I was able to see that it is coming (to avoid bad actions like casting domain providing card instead of waiting for Trade Routes).
Of course rush decks with mostly low level cards suffer from it (and sometimes decks with three domains, but usually they not).
Domain that opponent have from trade routes gives him domain that is not worse than his own since most cards require X domain anyway. When opponent cast 2nd trade routes it usually gives nothing to opponent, but result is that for two Trade Routes played (2 cards + 6 flux) you gain 2 domains and opponent gain one. So it's kind of getting 1 domain for 6 flux and two cards.

Trade Routes is OP!!! Make it more expensive and get rid of the domain for the opponent.

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Looking for: Crumbling Alone (2)
Also looking for: Revenant Bishop, Osin Faith Healer, Pilgrim's Cairn, Avenging Angel (2)

Altren:

I don't think you have ever had a problem with any deck...

Sure you lose some, but generally your 1337 skillZ and groovy decks overcome most obstacles. Try taking the perspective of us mere mortals in r/t OP cards, decks, and such. It will be a good exercise for your neurons. (Basically forcing you NOT to use some in resolving issues).

Humbly,

Gelatin of sometimes death

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