I don't know if you read the earlier posts by the devs, but they will allow players to light up that are potentially marked by your squad leader. Therefore, you actually have to actively locate your target before you can light him up in game. Although, he expressed they are trying this, it's not fully implemented yet.

This would most definitely be the best approach. To be honest, having floating name tags and an uber obvious colour coding system; not only is an immersion breaker, but is also unnecessary in a game that should require focus to be won, not speed.
As if the races and factions in the 40K universe aren't excrutiatingly obvious enough, we now have to go ahead and start colouring and tagging them all too?

I am totally incapable of differentiating between Eldar and Orks, or Ultramarines and Blood Angels /sarcasm.

Actually, it depends on how it is implemented. It has been brought up that in Space Marine, Chaos Marines were re-skinned space marines that walk and move in the same fashion. Blood Angels and Word Bearers bear similar color schemes. From up close it is very easy to tell them apart, but if you are say, 10 meters away, that's when it starts to get a bit tricky. Like I said, it should be optional. If you want to go for immersion, then don't do it. But if you want gameplay, then turn the option off. It is not that hard. And do not put down others for merely giving reasonable suggestions.

Sarcasm aside, what he said still holds weight.

If you're playing Eldar, it should be pretty obvious to not shoot Eldar. This isn't planetside where everyone is the same model colored differently. My friend is colorblind when it comes to blues and purples, so he plays the Terran Republic (Red color) to not have to worry about friendly fire. That should not be an issue with the 40k universe.

These are 3 distinct races (4th being Chaos) with different shapes, sizes, and armor. The Legions they picked don't look anything like their loyalist counterparts. If you cannot make out the detail between a Chaos Marine and a loyalist, then there's something wrong with the view distance. If a spiky marine is going at it with a non-spiky marine, then you should be able to infer that one is Chaos and the other isn't.

However, I'm not everyone so I also agree with what you said. There should be a way to change the color coding of everyone, sort of like how they do in RTS's. Where everyone is red, and your allies are blue. But that should be a toggle, not the default. I would much prefer there be a huge model distinction between the 4 factions than having to rely upon having them color coded. (See: Planetside 2)

(quotes not working for me right now)
I agree. But I feel that it should have the option. Personally, I will most likely not even use it, but I am thinking for players that might need to use it.

There's a problem with making it an option. Coloring all your enemies red (especially a bright red) gives you quite an advantage. This means the "immersive" option is at a disadvantage. Trust me, coloring everything you need to shoot the same color gives your eyes a much easier time.

Whether or not this should be an option depends on whether or not such an advantage should be allowed.

@All
please read the earlier posts guys, the current system is, there will only be color coding after a squad or strikeforce leader has marked a target after they have been identified. Therefore, you must legitimately see the target before targeting them. and you can only target a select few individuals at one time (more than likely, they won't have limitless marking).

If it was already answered then the thread should have been locked to keep it from going on longer than it should have.

I really hope we don't have a sea of red(enemy players) flooding our screens, along with another sea of blue/green(friendly players).

Behavior is striving for the largest multiplayer battles possible, so imagine trying to make out details and the game world around you with hundreds if not thousands of red/blue/green/yellow name tags and health bars overloading your screen. Not only is it a nightmare trying to see objects through all that name tag spam, it's a huge hit on your Frames per second. I've played a few other PVP centric games and experienced that first hand, though not on the large scale B.O. is striving towards.

Personally, I'd prefer NO friendly or enemy red/blue/green tags of any sorts while in combat. Friendly nametags and titles(Chapter/Squad/Accomplishments) should only show when it very close proximity to friendly players.

And as far as worrying about friendly fire, that's where situational awareness, communications and teamwork comes into play. If you can't make out a Space Marine from an Ork, well I don't know what to say about that. If you have targets so far in the distance you cannot make out friend from foe, you shouldn't be shooting.

I'd much rather have to distinguish friend vs foe by having to physically ID my targets, rather than having the game/system do it for me via arcade like RED icons, nametags, ect.

Yep - Locking the Thread should be a good idea
Color coding is primarily for HUD elements like map markers and Nametag icons. Then, some Wargears will allow you to mark some enemies - again this will probably to only a few enemies at the same time and it will feel really connected lore-wise with the wargear/Psychic power being used. These colors should be adjustable/tweakable for Color-blind persons or people that wants to use one color for all enemy factions. Again, nothing that breaks the immersion or that makes the gameplay easier for some people.