Hello. As a new player for the L5R card game, I have only two concerns about the FFG version. Game is too short, 4/5 turn is not engouh in my eyes and I wouldn't say no to more dynasty deck consistency. And the lack of choice for role card. I don't see why an event in US should limit my deckbuilding.
This was very true for the old game. And it was one of the main reason, i didn't play it. I'm a fan of L5R RPG and many online card game, but the CCG never actracted me. In fact, when I read some lore, I thought some stories in the last century of Rokugan were so... stranges. I had the feeling they were here merely for an CCG event. For me, the new L5R card game is more well-rounded. And I hope they'll not let player have an impact on the game balance. I don't think the number one in that tournament will think : "Hum, X is the best choice for my clan, but my clan is already one of the strongest one. Let's pick Y to make things more interesting." or "Let's pick Z, it makes more sens lore wise."
With LCG, clan fidelity will be less a thing. Be carefull about game balance or you might play against the same two clan 70% of the time.
Honestly if I want to play a game were player's performance have an impact on the game, I would rather play the RPG. I didn't like the CCG, but I think L5R 4th edition is great.