My understanding from Logress is that, other then the soul skills and will-o-wisp, our cards pretty much the same as they were in the Japanese game... when it FIRST came out. Apparently as the game has evolved with more sets their cards have changed many times to maintain balance, thus why many of our refess cards are so much weaker then theirs, they got buffed as more sets came out presumably the other clans got alot stronger necessitating the old refess cards be improved. Their personal stance is that currently the cards do not need said buff in the English game which has only the first set. The current state of the English meta would suggest other wise, but Logress has said that he is currently looking into this matter, with my understanding being that he is using both his own refess builds and builds specifically given to him by the Japanese players to see how capable Refess truly is of succeeding in our current environment.
Personally I'm only aware of one of the Japanese Refess decks and it was EXTREMELY rare(4 and 5 star) heavy, something I could spend 100 bucks worth of Gran on and possibly still not have all the cards necessary to be able to make, so that was a little discouraging, but I believe at least one of the Japanese decks isn't quite so rare heavy. If he has success with it maybe Logress will let us in on some of its secrets to success.
As for the other decks, with out playing them myself I can't say for certain how their fairing or comparing but I constantly play people of all 3 clans with winning records so I assume there all having some level of success. Yeah there are alot of popular combos many people are using, but again, we have only 1 set so far, the options available aren't exactly endless, and in any card game its common place that if some one finds something that works, most people will copy cat it until some one finds a way to beat it or something that works better.
There's definitely an issue finding opponents, and to me this has been for some time a big issue that's needing addressing and hasn't been. Last I heard the current stance we're supposed to take is just to wait for more people to level up. I've been waiting for some time and haven't seen significant growth in the number of players I have access to, but there's not really much we can do right now but endure. I understand that they want their new players to have a positive experience and not start out the game having their face beat in game after game by top level players but it still seems like the cut off at 9 is a little high. You said to increase the experience but to me that's just silly, reaching levels should mean something and not be something that's given away, instead just lower the room to 1-5 or something similar and bam, you've effectively doubled the rate at which players will join the non-beginner room.
The bunnies of Lavato have special abilities, like 'Action Skill: Make Carrot Disappear.'