As a Player, I greatly enjoy immersing myself into the settings and the scenarios. Investigation and problem solving are my favorite activities, but I don't shy from a fight. I make use of Skills and Talents and Combat Actions in such a way as to make combat seem more involved, more like a cinematic scene than a contest of dice rolling, turning the act of combat (in my mind, at least) into a swashbuckling encounter.

As a GM, I attempt to present combat situations from the same perspective. The Kill Team that I run are quite good at maximizing their abilities to face down foes in combat encounters, but I rarely see Combat Actions such as Maneuver, Knock-Back, Guarded Attack, etc. Many times it boils down to an Action being preferred only in game mechanic perspective, meaning if it doesn't provide the max bonus to a Skill Test it's not an option. As a Player, I've used Maneuver to make opponents fall into nearby fighting pits, freeing myself to advance from engagements with mooks to confronting the big nasty. (Can one Maneuver a Horde?) I've used Take Down to render opponents non-combative long enough to shackle them (arrest them). As a GM, it's more difficult to do these things, simply because they put the opponents I pit against the Players at a disadvantageous footing, meaning they do not optimize bonuses/buffs, and any further attempts to do these things have been quashed (by me) because a cinematic scene just ends up being a slice-and-dice massacre.

My question to the forum is: do other GMs see this occurring in their games, as well? I'm not griping, mind you. A combat encounter certainly can be nothing but a back-and-forth trade of Standard, Swift, Lightning, Semi-Auto, and Full Auto Attacks, and it reaches the same conclusion. The lack of "interesting" Combat Action use doesn't truly concern me, or affect the story, as long as the Players are enjoying themselves. But I get the feeling that, in general, many Combat Actions are…superfluous.

The reason I bring this question is because Swirling Ranged and Melee encounters actually aren't mobile, and I would like them to be. PCs and NPCs Dodging Ranged Attacks could be moved slightly (1 meter/1"…more in the case of Dodging AoE Attacks) to represent their new placement after attempting to Dodge an Attack. Foes that are Charged could be forced back by the same degree to represent temporary yet ultimately cinematic back footing, etc. Combat encounters sometimes remind me of playing Eye of the Beholder; everything is static, with clangs and grunts, until something dies with a croak of UUUUUGHH!

If you want to experiment with house rules involving knockback, I say run it by your players first. I could see it adding an interesting dynamic to fights, especially near high drops.

I rarely see many combat actions besides the straight forward aim and attack options. I suspect part of this is down to the W40kRPG system being inherently quite deadly, so the best option for staying alive is often to wipe out the opposition as quickly as possible. That said, I certainly see a place for actions such as disarm and knockdown but they're a bit too situational in comparison to the ever-useful "multiple attacks".

What about having your NPC/foes/badguys etc. use these actions? When the PC's notice that they can't hit an enemy that's using a guarded attack, or that they are being maneuvered out of the way or over a cliff, hopefully they will get inspired, or at least figure out that they have to change tactics in order to win the fight.

I once played a Storm Warden Assault marine (rank 1, bolt pistol and chainsword) who had the tenacity to challenge a Firewarrior commander (in battlesuit) to a duel. Suffice to say that i soon found his dual plasma rifle shots whizzing past too close for comfort, so i started using knockdown - i'd basically rush over to him using my jump pack and then smash him to the ground. He'd proceed to get back up, jump backwards and volley me again, but it kept the incoming fire to a minimum and let me do the odd wound here and there on the turn after i knocked him down (i was able to do multiple attacks on those rounds).
I believe i won (barely) with only a few wounds left, but got a righteous hit when i cleaved the armoured torso of his battlesuit in twain to reveal his mangled body as he sputtered out some crucial plot related info (it was typically duplicitous misinformation from the Tau). I felt very chuffed after pulling that off, and my Oath of Glory was fulfilled!

My point - straight forward attack actions don't always lead to victory.

My experience has been that my players only resort to combat actions other than straight-up Attack if they are losing, or an individual character is on the verge of dying…

Grapple-executions have always been popular for killing anything with a good set of evasion skills.

Otherwise the only other nonstandard combat action which sees a lot of use is takedown. Feint sees a bit of use, but grapple-execution is more popular.

I don't thinkI've seen knock-down or maneuver used seriously. Knock down is a well liked contemptuous attack though.