There's some fun stuff in this command expansion!
Simultaneous Orders: Might not get too much use at the moment, but this might be stellar pick later on in other units. It gets me rather excited for what's in store.
File Leader: Slightly expensive but with the right reading, you should be able to get the jump on an opponent's charge. Overall it might be too narrow or situational compared to all the other upgrades.
Captivating Hexer: Underwhelming and looks to be more acceptable on a smaller unit or flaker. I do feel that there's better options for the slot too.
Fallen Hero: I like this dude for both that extra hit point and the option of an extra upgrade for the unit.
Tactical Drummer: The effect is meh but that defense of 4 is very interesting. A unit featuring all of the high defense upgrades might be worth looking into.
Blighted Vexillum Bearer: It's been previewed before but I want to say how much I like this little guy. I really don't mind spending just 3 points to get out a free blight to a contacted enemy. One contact is enough to warrant the cost.
Raven Standard Bearer: I just love that defense of 4, but the effect will be interesting on the 3x2 unit of archer. I have to add that I'm not fully committed to running that size unit of archers (yet) but you can use this guy on the 2x2 unit with Ardus in the army too.