This is the stuff I'm really looking forward to trying out. I love FIFA's gameplay this year but hope I can learn to love PES's too, because FIFA's career mode improvements - training mini-games which are pretty repetitive and pre-season tournaments that are ultimately pointless - pale in comparison.
Does the Team Spirit feel realistic in terms of the boost / penalties it gives to you?
Hey, I've been lurking a lot, but I thought I would chime in on Master League. I'm doing a test ML right now with Barca (Won't start my proper one with Arsenal until the squad update) and I'm seeing some nice things I thought I'd share for people waiting for the update until they try ML.
First of all, finally I'm seeing realistic results!! I've played and simmed half a season with 15 minute matches and they've fixed the awful absurd high scoring games from last year! I'm seeing plenty of 0-0 draws, 1-0 wins and realistic high scoring results like the odd 5-1, 4-2. And I'm seeing this across every league.
The results and player stats also mimic real life quite well; Madrid and Barca are top of La Liga with barely 2 points difference between them. Ronaldo and Messi are the top scorers with 17 Liga goals each at the half way point of the season, with Messi having the most assists in the league. Chelsea and Man City are dominating the EPL with Arsenal... in 4th

And Diego Costa is the top scorer with 16 goals.
And these more realistic stats and results are being seen across all the leagues with nothing really standing out as fantasy (yet)
As for Team Spirit: from what I can tell, it's not a moral mechanic, it's all to do with the tactics you use and how well the players fit those tactics.
For instance, I had a team spirit of 95 with short pass/possession tactic, I then changed it to Long Ball and the spirit dropped to 84, I then changed to Counter attack/Long ball and it dropped to 75! I changed from Frontline pressure to All out defence, and again, the spirit dropped significantly. And of course the spirit changes dramatically based on the lineup.
So basically, playing direct, counter attack football with Barca is a no go; they don't have the players to pull it off. But play them with short pass and possession and the best 11 that suits that style of play and the team spirit goes through the roof.
Team spirit also affects derby/rival matches a lot. When picking the team for these matches, some players will have flashing condition symbols indicating that they are the best players to pick. Don't put them in the starting 11 and team spirit drops a lot. The AI also does the same for the big matches; they pick the best team that suits their tactics and players that will be on form for the big games. I can only hope and pray the AI has the same mind when using the transfer market, as that would obviously add a lot of depth to the way AI teams build their squads.
Player roles also affect Team Spirit, but I need to play around with that more.
The monthly squad reports are also great! they give you plenty of stats on the way you've played that month. Just for instance I discovered I NEVER cross the ball and spend 38% of the match on the right side with Messi and Alves. The reports will really help you understand how you play, why you play that way, and how successful that style of play has been for the players you use.
More tidbits:
Players now age up in January instead of at the start of a new season.
I'm not seeing many injuries at all, sadly. But this is down to the lack of fouls more than anything.
Teams make transfer bids for your players all season, not just during the transfer window.
The commentary was talking about how successful my first season in charge at the half way point has been. It's nowhere near the level of detail that's in Fifa's CM, but it's a step in the right direction.
Sadly no transfer deadline countdown like in Fifa. I always enjoy that but oh well.
Anyway, as you can tell from my long post, I care a lot about Master League and I think Konami have finally given it some love. It's not the broken mess it was last year and the new features and slicker menus make it as addictive as ever.