Was the game mechanics changed?

I've had some strange feeling, that the AI mechanics had some serious tinkering recently. The thing is, that the AI tends to choose 5-gem matches now more often over the 4-in-a-row matches, which is nice. My experience is, that since that change, the AI has much more frequently 4+ cascades out from single 3 gem matches (a significant amount of them can't be calculated out with just the gems on the board), which isn't so nice. I've also noticed that tihis occurs more frequently when i'm paired with an opponent with lesser rank in the event leaderboard (that can be a coincidence though).

Anyone noticed this or am i imagining things?

Anyway, my Gideon has RC now, with Rouge's Passage. I wanted to avoid that because i don't think it's fair, but if the game itself isn't fair then why bother? I also dropped in some plus surprise for the blockers, just in case. First in the Rai event, now in this event too i'm falling behind because reasons beyond me, so i don't feel the usual urge being nice anymore. Especially when i saw players on the upper end of the leaderboard using RC and seasons past deliberately.

Some plus info for RC: Draina with Haunted Cloak vs. RC: RC wins, fatality. Reasons beyond me, my thought was that the RC didn't consider the first strike as a block and in the phase where it striked Draina it took no damage, so it stayed (with prevent damage on it of course).