Let me start with the negative so from there it can only get better.
The sanguinary guard sprue.
Almost everything on here is great. Love the wings/single nozzle jump packs. Love the torsos and weapons. Wish there had been more stiletto type blades still, but whatever. REALLY happy to see axes. What I am disappointed with is 2 things.
1- I am not convinced with the heads. Not all of them need to look like Dante. A spiffy mask would have been enough. No crest needed. However, this may change once I see the faces.
2- The banner. While this is great for everyone else, I am somewhat disheartened myself by it. Why? Because I already freehanded it. And now most likely the squad it is in won't be taking it. I have a feeling based off this banner that honour guards are out and sanguinary guards are in and that based on other pictures, sternguard and vanguard now have the gold helmets.
Really, I am being selfish with the banner, but now everyone and their mom will have a well painted BA banner, making mine look insignificant in some ways, and also making mine redundant.
Next thing: Red Thirst. A 1 in 6 chance of furious charge/fearless isn't something to bank on and Seth is really the only way to make it truly great. And as I have stated before, I really only wanted to use Blood Angel characters. But I will probably be using Seth. The plan I have is to convert up a model to represent him and use that as my 2nd Company Captain.
Final Bad bit: No Eternal Warriors. Just generally bummed that Dante can still be offed by a power fist. The only thing that can cover this is if you can take Sanguinary Guard as a retinue, which I am hoping for, rather than just attaching him to a squad.
Mephiston looks really tough, but still enough landed power weapons will end him.
GOOD STUFF
Chaplains/Lemartes as Elites/Upgrade Characters. This means I no long have to use up an HQ slot everytime on a Chaplain. I am happy that I can now play around and choose what I want in the most restricting part of the force org.
Sanguinary Priest as an elites. Cool I think. Probably can attach each to a squad if you want. Just generally good. And allows you to take a few without using up HQ once again. Also glad to see them brought back, as they were missing in the PDF version.
Scouting Baals. Broken but awesome. Every BA tourney list will probably have 3 of these things, most likely with flamestorms and heavy flamers.
Troop Dreadnoughts. Even if they aren't scoring, it is a nice way to work furiosos into an army without using up Elites slots better used on sanguinary guard, vanguard and Sang Priests.
Stormraven. Glad to see it. Not as broken as we all thought it would be. Much more limited as a heavy support as well. But still a really cool concept and I am sure the model will be awesome.