Eternity is going to create unhealthy binary patterns on battle mages (concern, not a rant)

Scenario A:

A battle mage( , and others) gets some lead, due to help from jungle, outplay, buffs or being in a good matchup. They rush some item, because those are their core after the rework. They can now enter fights freely, being almost unbeatable and spending almost no resources on them due to Eternity passive. They keep snowballing, with ease.

Scenario B:

A Battle mage( , ) gets a bit behind, due to being ganked, outplayed, nerfed or in a bad matchup. They rush some item, because those are their core after the rework. Because they are behind, they will avoid entering fights - Eternity is now almost useless for them most of the time. When they finally enter the fight, positive feedback loop of Eternity doesn't have enough time to kick in, because of their lower health and mana pools. They keep falling behind, hard.

I know that snowballing is part of the game, but Catalyst of Aeons with new Eternity passive is different than other sustain items - it is most powerful when you are fighting someone, it is below meh when you don't. I'm afraid that intended reliance on it will turn battle mages into very snowball-focused champions, which isn't too nice for the game, and also doesn't fit those champions current playstyle and thematic - right now, battle mages will get to their strong point on power curve, unless you literally flame horizoned them, but they won't go Riven- or Zed-style snowballing with just a little lead - they are very reliable champions, but with little possibility of snowballing into solo carrying games. They are reliable teamfighting beasts, which is what a battle mage is supposed to be.