The Good
This DLC did a really good job at setting the atmosphere for 1940, you really feel like you are just rolling over the Russians in the beginning, then as the weather begins to change it gives you just the right amount of frustration with logistics issues, and finally by the last few scenarios you really feel like the situation vis a vis your relative power against the Russians has suddenly changed. To me this was the best thing about the DLC.
Yugoslavia and Greece, not much to say other than that I really like having this theatre of war in the game. Not particularly hard or challenging but its always fun to have a warm up for the main event

Crete, holy cow, this was the first scenario in the DLC where you really get a curve ball thrown at you. I hope you have been training up some good fallschirmjaegers because you are going to need them. And when they scenario tells you that you probably won't be able to use transports they really mean you aren't going to be able to. I used three level bombers and 5 paratroopers to get the job done. Nice change up.
Training scenario, these are a really good addition to the game. Nothing was worse than having units purchased late in the game that never amounted to much because you just couldn't make them experienced enough, these scenarios really help. Just a suggestion but when you are training up your units make sure to put them on the high ground when attacking the targets so you benefit from the bonuses. Also, make sure to rearrange your heroes before and after. This can make a huge difference in how much experience you get.
Sturer Emil, this AT gun is just brutally effective. I gave mine the following heroes: overrun, camouflage (really helps you not take damage and that is so important with only 9 replacements), and double support. Just god levels of AT support and was able to get him steamroller. This unit was able to kill 435 points of worth of armor over the course of a single DLC, a must get unit.
Commendation point indicator, this is a really nice addition to the UI.
The Bad
This really isn't all that bad, and in some ways is rather good, but was anyone else a little sad that their Verdeja is not going to be a sustainable useable tank by the end of the next DLC? It is the only unit that has made it through all the previous DLC without being upgraded. I would suggest though that you don't update it yet because that extra speed actually really is useful. But man I don't want to upgrade it.
The Moscow scenario, it is a good scenario and it is very flavorful, BUT after the Warsaw scenario I just don't think it had enough meat to it. This should have been another 50 turn grind with a large city to try and root out just a ton of dug in infantry. A minor let down but that scenario is still really hard.
The Ugly
Really didn't like Haptmann Wagner dying half way through the DLC. It does add a little drama to the whole thing but honestly I like his briefings and frankly having been in the army I don't really need a reminder of the human cost of war while playing a game. But at least it was done well and rather poignantly.
The game is still balanced around prestige which I think is a really bad design choice. They should have stuck with the different levels of victory and loss. It is just my two cents but playing on Generalissamus I now have almost 170k prestige in the bank and I am guessing I am not the only one. Removing the tension of turn/time requirements to get things done on the battlefield in my opinion really removes a lot of the challenge in the game. I realize that a lot of the commendation point bonus objectives for all intents and purposes take the place of this but it doesn't have the same effect. I could say more about this but the bottom line is the game would have been better if the major and minor victories had been kept in the game.