Your preference in terms of mechanics, season 1 or season 2?

Season 1 is great, and it's the whole reason I got into KI, and while I don't agree with every change Season 2 has made, on the whole I prefer Season 2.
Main reasons are as follows:
- More character variety and diversity
- Single hit damage boost makes it a more skilled game (anti-airing is rewarded, starting a punish with fierce instead of jab matters a lot)
- S1 had more of a focus on short combos and one-chance-breaks. S2 still has quite a bit of that (which is fine), but they are trying to force you into playing the combo breaker game if you want big damage, and I personally find combo breaking a really interesting part of KI. It adds a lot of stress to the match, it's hard, and it frustrates opponents on a psychological level (despite being risky and punishing when you're wrong) more than most other fighting game mechanics I can think of. Not everyone I've talked to loves the combo breaking mechanic, and S2 still lets you play by doing short combos and trying your best to ignore that system, but if your opponent has decided he is going to force you to break combos to survive, I like that aspect of the game. The reward for being right on offense (counter-breaker, lockout) is really fun to me, and I have numerous other games I can play (and have played for 15 years) if I want to play a game without combo breaks, so I like that S2 is trying to bring the focus back on that a bit. S2 is, IMO, a pretty solid mix between unbreakable setups for all your resources, one-chance for small damage into a setup, or going for the big damage but exposing yourself to breaks.
- I think stuff like soft knockdown on combo breakers and less meter overall really impact the flow/decision making of the game in positive ways.