So with the last EX Episode pack released and a patch sent out recently for the game, here's what I can say:
- The final match against Leon for the individual episodes is a VERY rough battle if you aren't fully prepared... and is probably still rough even after that. I managed to outdo her with an S2 Yukiho at Level 40, but I literally needed to rank up from S3, get a perfect combo, AND find a very specific way to abuse the AI that changed almost every other time I played. I imagine taking her on with the S1 rank-up completed (which is against MAI and something I haven't even attempted yet) would make it smoother, but I think you still need to be mindful of counters and bursting at the right time.
- Maybe I'm silly for expecting more from it, but all you seem to get from it is Leon's new song and extend... which can't even be mixed with her original outfit and Acceleration. Considering this carries over for every idol and only unlocks after that last challenge, I'm pretty disappointed they ended it off with this.
- There was a recent patch for the game which I think added in a "True Leon" match as a special S1 job alongside the DLC jobs. She has the same crazy burst skill that she does in the EX Episodes on top of perfect stats (literally, every bar is filled), but the format makes it far easier for me. I beat her on my first try because it's just a regular festival otherwise, so it's just a matter of spamming memories like crazy. There's no additional prize as far as I know, just bragging rights and more job rewards if that makes you happy.