Hello Streum Studio,
Firstly I think you made a marvelous game. The Single Player is so-so but playing the Multiplayer with friends on max difficulty with FF turned on is an awesome challenge. The way you guys have continued to support the game has been surprising and delightful. I'm really looking forward to the next patch coming with the special edition.
The main suggestion I had is very simple (I think) you should implement some sort of obvious sign to other players that The Chaplains 2nd skill is active. This could be as simple as an icon on the everyone's hud or as glorious as the squad being bathed in light whilst The Chaplain bellows out a holy write of vengeance.
I think the Thunder Hammers damage should not travel backwards. Whilst hilarious this makes the Hammer virtually useless when FF is turned on which is silly since canonically Terminator Assault Squads fight in close ranks in 10 man squads and don't all kill each other with every blow.
These are the only two changes I would reasonably suggest.
A wish list of things to include would be Combi-Bolters of all the different varieties, The Halberd of Caliban, the ability for one player to spawn as Belial for a little bit, a new Deathwing Ancient class and the addition of some on the rails AI allies sections were you get to feel like a full 10 man Terminator Squad purging the unclean.