Dear Focus Home Interactive and Tindalos Interactive,
If you release this game, I absolutely promise you it will get slammed on Steam reviews, on forums, and on youtube. The most you could hope for is mediocre reviews from the big review sites. Both the PVE and PVP community have legit complaints that must get fixed before they spend money and commit to this game.
PVE
1.) People want their Skirmish back from the first game. You should be alarmed with how many people are saying this.
2.) Campaign needs more customization. More unlocks, skins, trail colors, sounds, tags, captains, skills and so on.
3.) Don't release a bugy co-op campaign. You have already hinted as much, claiming it to be a soft roll out with a march release. It doesn't sound good, and if it is so bad that you need to pull it or delay it after release it's not going to go over well.

PVP
1.) Their must be more depth to the PvP. Capture the Flag, Control Points, King of the Hill, Team Death Match, Search and Destroy, 1v1, 2v2, 1v1v1v1, 1vAI, 2vAI, let us make custom games, let us host public games, let us que up and fill slots.
2.) Ranked needs to be overhauled. Much of what is desired above could work here. Different game modes and ways to play. Ones Rank should work like it does in most mobas, bronze 1 bronze 2 silver 1 silver 2 1v1 rank 2v2 rank and so on. Spread out the modes so we aren't doing the same thing or even lets us que up and rank up in each mode separately.
3.) We should have a profile with a stats screen to see some information about our play. What ships we use most, which faction, favorite ability, win loss ratio, match history.
4.) Let us make ARMADAS! Just like a guild in MMOS, let us make Armadas where we can group up and que together, run skirms, recruit people, make a 3 letter tag and logo.

Game In General
1.) We should have a account profile level where we can unlock profile pictures, tags, ship skins, emotes, factions cards for anything we do while we play.
2.) We should have a way to track stats across PVP and PVE, a snap shot of how we play.
You have a fantastic game in a beloved franchise, I think many would agree that we are willing to wait but if you release it now and try to fix it over time, it will be too late to recover the player base. Add some things, run a few Pre-Order only Betas, then run and open beta then release. All the while being completely transparent and active with the community and I promise, you may very well have the greatest 40k video game ever made.